You are given a science question (easy-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.

[EX Q]: When a tree suffers from a decreased ability to transport materials within the phloem, what is directly impacted?
(A) volume of water in the xylem (B) flow of necessary nutrients (C) response to environmental factors (D) rate of photosynthesis in leaves
[EX A]: B

[EX Q]: A class made a solar cooker out of a large can. What color should they paint the can in order to collect the most heat?
(A) black (B) green (C) pink (D) white
[EX A]: A

[EX Q]: Indigo buntings are birds that nest in Florida during the summer. Male buntings are bright blue in color while females are a dull brown. How does the dull brown color of the female buntings help the species survive?
(A) It helps male birds find a mate. (B) It helps the birds find food more easily. (C) It helps hide the birds while they sit on their nests. (D) It helps the birds find the flock when migrating.
[EX A]:
C