Which Statement describes a controlled experiment? A. It includes two groups, neither of which is exposed to the factor being tested.
B. It includes a group exposed to one of factors being tested and a group that is exposed to another of the factors being tested.
C. It includes a group exposed to the factor being tested, and a group that is not exposed to the factor being tested.
D. It includes two groups, both of which are exposed to the factor being tested.

( Please hurry, im being timed!)