Question1 Below are 25 multiple-choice questions, each with ONE correct answer and is worth 2 marks. You are advised against looking for the perfect answer, but for the best answer in the list. 1. A company first summarizes past sales trends and then investigates reasons for a sudden decline in one region. The second activity is best described as: Select one alternative: Descriptive analytics Diagnostic analytics Predictive analytics Data engineering 2. After performing a left join between a customer table and a transaction table, some transaction variables become missing. Which explanation is most appropriate? Select one alternative The dataset has been normalized Binary variables cannot be merged Measures cannot be merged with dimensions Some customers have no matching transactions 3. Which situation most strongly suggests that a variable should be treated as categorical rather than numeric? Select one alternative The variable contains decimal values The variable measures revenue The variable contains product IDs The variable represents ordered months 4. Which action is most likely to introduce selection bias during data preparation? Select one alternative Removing duplicate records Filtering observations based on analytical relevance Standardizing variable formats Deleting outliers without business justification 5. After unpivoting a dataset, which structural change typically occurs? Select one alternative Fewer rows and more columns Automatic aggregation of measures Removal of categorical variables More rows and fewer columns 6. An analyst applies 1% two-sided winsorization to a dataset containing income values. How are the extreme observations processed? Select one alternative The lowest 1% of values are replaced with the value at the 99th percentile, and the highest 1% are replaced with the value at the 1st percentile The lowest 1% of values are replaced with the value at the 1st percentile The lowest 1% of values are replaced with the value at the 1st percentile, and the highest 1% are replaced with the value at the 99th percentile The lowest 1% and highest 1% of observations are removed from the dataset 7. Which modelling design best supports flexible slicing of sales performance by region and time? Select one alternative Pivoted summary table Fully normalized transactional schema Star schema with separate dimension tables Single flat table 8. A dashboard shows duplicated total sales after creating a many-to-many relationship between tables. The most likely cause is: Select one alternative Insufficient data normalization Double-counting due to relationship ambiguity Missing calculated measures Incorrect visualization type 9. Which of the following is NOT true about cardinality types in Power BI?Select one alternative One-to-many relationships are the most common type for linking fact and dimension tables Many-to-many relationships are directly supported in Power BI and frequently used in modelling One-to-one relationships only occur when both tables have unique values in the related columns The choice of cardinality impacts the cross-filtering direction between tables 10. In data modelling, which tool would you use to create a DATE table in Power BI? Select one alternative DAX function Power Query editor New Measure Navigator view 11. Which situation best justifies creating a calculated column instead of a measure? Select one alternative Comparing performance across different filters Building interactive KPI cards Calculating total sales in a dashboard Flag large orders based on the number of units sold 12. Use DAX to flag customers as “High Priority” when OR (AND (Sales > 1000, Region = “NSW”), LoyaltyScore > 80) Which customer will be flagged? Select one alternative Sales = 800, Region = NSW, LoyaltyScore = 75 Sales = 1000, Region = NSW, LoyaltyScore = 85 Sales = 1500, Region = VIC, LoyaltyScore = 60 Sales = 900, Region = NSW, LoyaltyScore = 70 13. Which of the following statements about the DIVIDE() function in Power BI DAX is correct? Select one alternative DIVIDE() returns the result of dividing the numerator by the denominator, and it handles division by zero gracefully by returning a blank value. DIVIDE() returns an error if the denominator is zero, making it necessary to handle such errors separately. DIVIDE() is not a valid function in Power BI DAX; you should use the "/" operator for division. DIVIDE() always rounds the result to the nearest whole number. 14. Which of the following scenarios is best suited for a scatter plot in Power BI? Select one alternative Tracking monthly revenue trends over a financial year Examining relationships between sales revenue and advertising spend across multiple regions Comparing market share among suppliers in a specific year Showing the proportion of sales by product category 15. You want to compare the relative contribution of product categories to total sales over time and observe their trends. Which visualization should you use? Select one alternative Waterfall chart Grouped bar chart Stacked area chart Line chart 16. A marketing analyst wants to explore clusters of customer behavior by analyzing the relationships among annual spending, purchase frequency, and customer lifetime value. Which visualization is best suited for this task? Select one alternative Pie chart Bubble chart Tree map Dual-axis bar chart 17. An analyst uses a pie chart to display the market share of 15 competitors. What is the primary limitation of this design? Select one alternative Market share must be shown using line charts Pie charts automatically distort data values Pie charts cannot display percentages Too many slices reduce interpretability and comparison accuracy 18. A time-series dataset is visualized using a clustered bar chart. Compared with a line chart, what analytical insight is most likely weakened? Select one alternative Exact value comparison Category ranking Identification of outliers Detection of continuous trend patterns 19. A dashboard uses a scatter plot to compare sales performance across regions, but each region has only one aggregated value. What is the most appropriate improvement? Select one alternative Change colour palette Convert to a bar chart Add gridlines Increase marker size 20. What is the primary purpose of a waterfall chart in Power BI? Select one alternative To illustrate part-to-whole proportions across categories To show relationships between multiple numerical variables To compare categorical data side-by-side for analysis To display running totals and the impact of individual contributions to a metric 21. What is the primary focus of the design principles of accessibility in the context of data visualization? Select one alternative Making data visualisations understandable and usable by individuals of diverse backgrounds. Optimizing the speed at which users can interact with the visualizations. Ensuring that data visualizations are visually appealing. Reducing the complexity of data visualizations to lower implementation costs. 22. A dashboard contains dense gridlines, heavy borders, and repeated legends. What is the primary negative consequence? Select one alternative Lower query performance Higher cognitive load for users Reduced data accuracy Increased storage requirements 23. A visually appealing dashboard contains heavy decorative elements that distract users from key insights. What is the main design issue? Select one alternative Over-aggregation of measures Misuse of time hierarchy Aesthetics overriding analytical effectiveness Incorrect chart selection 24. A dashboard highlights only favorable performance indicators while omitting declining metrics. What is the most significant ethical risk? Select one alternative Inefficient pre-attentive attributes Selective reporting leading to biased decision-making Increased report complexity Violation of data normalization principles 25. Which potential misunderstanding may occur when audiences are unfamiliar with log scales of Y-axis? Select one alternative They may think the chart shows categorical data instead of numerical data They may underestimate differences in small values and overestimate differences in large values They may assume equal vertical distance represents equal absolute change They may be confused with the legend and colors ResetMaximum marks: 50 Select one alternative Waterfall chart Grouped bar chart Stacked area chart Line chartSingle choice