Consider the below variables from the survey data set. From the list, select the variable(s) that is/are ordinal categorical variables.多项选择题

a. Writing hand span (distance from tip of thumb to tip of little finger of spread hand, of writing hand, in centimetres)

b. Age (age of the student in years.)

c. Pulse (pulse rate of student: beats per minute)

d. Smoke (how much the student smokes: Factor, levels “Heavy”, “Regul” (regularly), “Occas” (occasionally), “Never”.)

e. Non-writing hand span (distance from tip of thumb to tip of little finger of spread hand, of non-writing hand, in centimetres)