Study the set-ups shown below. Each test tube contains few bean seeds on the cotton wool. Farheen wants to carry out an experiment to show that warmth of the light is needed for germination to take place. Which of the two set-ups should she use?

Study the set-ups shown below. Each test tube contains few bean seeds

1.	Study the set-ups shown below. Each test tube contains few bean seeds on the cotton wool. Farheen wants to carry out an experiment to show that warmth of the light is needed for germination to take place. Which of the two set-ups should she use?
A.	P and W
B.	R and W
C.	Q and W
D.	W and X
Answer» B. R and W