In experimental design, what term refers to the cause that scientists manipulate to observe effects?

In experimental design, what term refers to the cause that scientists manipulate to observe effects?

• A. Dependent variable
• B. Trend
• C. Independent variable
• D. Stable

Answer: (C)

In experimental design, the independent variable is the factor you deliberately change to see its effect. By controlling this variable, you’re testing whether changing it leads to a change in the outcome you measure—the dependent variable. The dependent variable is what you observe and record, not what you manipulate. A trend is a pattern you might notice in data, not the thing you actively change. Stable isn’t the term used for a manipulated variable. For example, if you’re testing how the amount of sunlight affects plant growth, the amount of sunlight is the independent variable, and plant height (the growth) is the dependent variable. Keeping other factors constant ensures any observed changes in growth are due to differences in sunlight, not other variables.

In experimental design, the independent variable is the factor you deliberately change to see its effect. By controlling this variable, you’re testing whether changing it leads to a change in the outcome you measure—the dependent variable. The dependent variable is what you observe and record, not what you manipulate. A trend is a pattern you might notice in data, not the thing you actively change. Stable isn’t the term used for a manipulated variable.

For example, if you’re testing how the amount of sunlight affects plant growth, the amount of sunlight is the independent variable, and plant height (the growth) is the dependent variable. Keeping other factors constant ensures any observed changes in growth are due to differences in sunlight, not other variables.