Which variable changes because another variable is changed?

Correct answer: Dependent variable

The direct answer is C, the dependent variable. A variable is any feature that can change. The independent variable is the factor the investigator deliberately changes. The dependent variable is the response that changes because of that factor and is usually measured. A controlled variable is kept the same, and a constant is another name for something held unchanged. Step by step: identify the deliberate cause; identify the measured effect; the measured effect depends on the cause; therefore it is the dependent variable. A is wrong because a controlled variable is not supposed to change. B is wrong because the independent variable is the cause or input, not the response. C is correct because it changes as a consequence of another variable. D is wrong because a constant remains unchanged. Example: if fertiliser amount is changed and plant height is measured, fertiliser amount is independent and height is dependent. Exam cue: “what is measured?” usually points to the dependent variable.