Final answer:
The factor in an experiment that is deliberately modified is called the independent variable, and its effect is measured on the dependent variable, while control variables are kept constant.
Step-by-step explanation:
The term for the factor in an experiment that is deliberately modified while keeping all other factors unchanged is known as the independent variable. It is this variable that the experimenter manipulates to see how it affects another variable, which is the dependent variable. The control variables are those that are kept constant throughout the experiment to ensure that any impact on the dependent variable is due to the manipulation of the independent variable alone.
When conducting an experiment, researchers may use a control group that does not receive the experimental manipulation. This is in contrast to the experimental group that does receive the manipulation of the independent variable. By comparing the outcomes in these groups, researchers can infer the effects of the independent variable on the dependent variable, isolating the effect from other potential factors that are controlled across groups.