The variable that can be changed or manipulated in an experiment or study is called the independent variable.

Explanation:

• Independent Variable: This is the variable that the researcher changes or controls to observe its effect on another variable.
• Dependent Variable: This is the variable that is measured or observed to see how it responds to changes in the independent variable.
• Controlled Variables: These are variables kept constant to ensure that the effect on the dependent variable is due only to the independent variable.

Example:

If you are testing how sunlight affects plant growth:

• Independent Variable: Amount of sunlight
• Dependent Variable: Plant growth (height, biomass, etc.)
• Controlled Variables: Type of plant, soil, water, temperature

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