What are the roles of the two test groups in this
investigation?
A. Both are experimental groups, and each
Individually shows the effect of the direction
B. Dhe is the experimental group and one is the
control group, and together they show the
ellect of the direction of light.
C. Both are control groups, but only Test Group)
shows the effect of the direction of light.
D. Both are experimental groups, but only Test
Group 1 shows the effect of the direction of
light