The variable that is measured and affected by the changed variable is called the?

• A. Dependent variable
• B. Independent variable
• C. Pulse
• D. Blood pressure

Answer: (A)

In experiments, you change one factor and watch how another factor responds. The factor you deliberately change is the independent variable, while the factor you measure to see the effect is the dependent variable. Since the question asks for the variable that is measured and affected by the changed variable, the term that fits is the dependent variable.

For example, if you test how caffeine affects heart rate, caffeine is the independent variable and heart rate is the dependent variable. Pulse and blood pressure are specific measurements that could be the dependent variable in different experiments, but they are not the general term themselves. The independent variable, by contrast, is the one you control, not the one you measure.