Question at position 16 For the relationship represented in the figure below, which of the following is true? A department can have more than one employee. A department must have at least one employee. An employee can work in more than one department but does not have to work for any department. An employee has to work for more than one department.

Question

BlackTom AI · Accepted Answer

The crow’s-foot “fork” on the department side indicates that a department may be related to many employees.

1) Relevant knowledge points and symbols
- Crow’s-foot (three-pronged fork) at an entity end = “many” (0..* or 1..* depending on optionality marker).
- Single perpendicular line (|) = “one” (exactly one; mandatory).
- Small circle (O) = “zero allowed” (optional).
Reading each end together gives the cardinality and optionality for that end of the relationship.

2) Step-by-step reasoning from the diagram
- Look at the connector near DEPARTMENT: it shows the crow’s-foot shape pointing to DEPARTMENT. That symbol means “many” on the EMPLOYEE side with respect to DEPARTMENT (i.e., one department can be associated with multiple employee instances).
- Look at the connector near EMPLOYEE: it shows a circle (optional) plus a single-line marker toward DEPARTMENT, which indicates an employee is associated with at most one department and that association may be optional (0..1).
- Combining both ends: the relationship is one-to-many from DEPARTMENT to EMPLOYEE (a single department can have many employees), while each employee is related to at most one department and may have none.

3) Intermediate interpretation steps (symbol → meaning)
- Crow’s foot at department end → department side supports many employees.
- Circle at employee end → the employee’s participation is optional (zero allowed).
- Single line at employee end toward department → if participating, an employee links to at most one department.

4) Why the correct answer is correct
Because the crow’s-foot on the department side explicitly indicates multiplicity “many,” the statement “A department can have more than one employee.” is true.

5) Why the other options are incorrect
- “A department must have at least one employee.” Incorrect: the optional marker (circle) allows zero employees for a department, so it’s not mandatory.
- “An employee can work in more than one department but does not have to work for any department.” Incorrect: the employee end does not show a crow’s-foot (many); it shows at most one (0..1), so an employee cannot work in multiple departments.
- “An employee has to work for more than one department.” Incorrect: this contradicts the single-line/optional marker which limits an employee to at most one department and does not require multiple.

6) Conclusion
The diagram denotes a one-to-many relationship where a department can have many employees; therefore the correct answer is: “A department can have more than one employee.” This matches the provided answer.

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