Which option incorrectly matches a variable with its role?

Correct answer: Measured time as controlled variable

Direct answer: Option D is correct because it gives an incorrect role. A variable deliberately changed by the investigator is independent; a measured outcome is dependent; a condition held constant is controlled. Option A is correct matching: changed light is the independent variable. Option B is correct matching: measured height is the dependent result. Option C is correct matching if the same water amount is maintained throughout; it is then a controlled variable. Option D is incorrect because measured time is an outcome, so it should be a dependent variable, not a controlled variable. The word “measured” is an important clue: it usually points to the result being observed. A controlled variable is not the result being measured; it is a condition kept unchanged to make comparison fair. Memory cue: change it = independent, measure it = dependent, hold it constant = controlled.