What is the term for the variable that is intentionally manipulated in an experiment?

What is the term for the variable that is intentionally manipulated in an experiment?

• A. Dependent variable
• B. Independent variable
• C. Control variable
• D. Extraneous variable

Answer: (B)

The main idea here is the variable that researchers deliberately change to see its effect. In an experiment you set or adjust this variable to observe how it influences something you measure. That variable is the independent variable; it acts as the input or cause you’re testing. The outcome you observe and quantify is the dependent variable. To keep the test fair and focused, other factors that could affect the outcome are kept constant, called control variables, while any other unaccounted-for factors are extraneous variables that can introduce unwanted noise. For example, if you’re studying whether fertilizer affects plant height, you alter the amount of fertilizer (independent variable), measure how tall the plants grow (dependent variable), keep sunlight, water, and soil consistent (control variables), and try to minimize other influencing factors like pests (extraneous variables).

The main idea here is the variable that researchers deliberately change to see its effect. In an experiment you set or adjust this variable to observe how it influences something you measure. That variable is the independent variable; it acts as the input or cause you’re testing. The outcome you observe and quantify is the dependent variable. To keep the test fair and focused, other factors that could affect the outcome are kept constant, called control variables, while any other unaccounted-for factors are extraneous variables that can introduce unwanted noise. For example, if you’re studying whether fertilizer affects plant height, you alter the amount of fertilizer (independent variable), measure how tall the plants grow (dependent variable), keep sunlight, water, and soil consistent (control variables), and try to minimize other influencing factors like pests (extraneous variables).