If a scientist changes the amount of fertilizer to test plant growth while keeping all other factors constant, the fertilizer amount is the what?

If a scientist changes the amount of fertilizer to test plant growth while keeping all other factors constant, the fertilizer amount is the what?

• A. Dependent variable
• B. Independent variable
• C. Control variable
• D. Experimental result

Answer: (B)

When you study how changing one factor affects another, the factor you actively change is the independent variable. Here, the scientist is adjusting the amount of fertilizer to see how it affects the plants, so fertilizer amount is the independent variable. All other conditions—like light, water, soil type, and temperature—are kept the same to ensure any change in growth is due to the fertilizer alone. The plant growth you measure is the dependent variable—the outcome that responds to the manipulated factor. Control variables are those constant factors that keep the experiment fair, and the experimental result is the data you collect from observing plant growth.

When you study how changing one factor affects another, the factor you actively change is the independent variable. Here, the scientist is adjusting the amount of fertilizer to see how it affects the plants, so fertilizer amount is the independent variable. All other conditions—like light, water, soil type, and temperature—are kept the same to ensure any change in growth is due to the fertilizer alone. The plant growth you measure is the dependent variable—the outcome that responds to the manipulated factor. Control variables are those constant factors that keep the experiment fair, and the experimental result is the data you collect from observing plant growth.