5. In a scientific investigation, a scientist is testing to see
the effect of light intensity (strength of the light) on
plant growth. During her investigation, the scientist
ensures that all subject plants get the same amount of
water, are planted in the same type of soil and placed
in a lab room at the same temperature. Each of these
factors are an example of a
A) control group
B) experimental group
C) control variable
D) independent variable