Which variable is manipulated by the researcher in an experiment?

In an experiment, the variable that the researcher actively manipulates is known as the independent variable. This is the factor that is changed to observe its effects on the dependent variable, which is the outcome being measured. By systematically altering the independent variable, researchers can identify cause-and-effect relationships in their studies.

For instance, if a researcher is investigating the impact of a new medication on blood pressure, the medication dosage would be the independent variable. By adjusting this dosage, the researcher can determine how it influences blood pressure, the dependent variable in this scenario.

The other terms mentioned, such as controlled variables, refer to elements that are kept constant throughout the experiment to ensure that any changes in the dependent variable can be attributed to the manipulation of the independent variable. Responding variable is another term for the dependent variable, reflecting its response to changes made in the independent variable.