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.

[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
[A]: B


[Q]: Scientists found fish fossils in the desert. What do the fossils tell about this environment when the fish were alive?  
 (A) There was a forest with large trees. (B) There were lakes with water plants. (C) There were mountains with glaciers. (D) There was a desert with large rocks.
[A]: B


[Q]: In a lab investigation, a student notes that two metal blocks have the same mass. Based on this observation, if the two blocks were put on opposite sides of a balance, they would best represent  
 (A) balanced forces. (B) unbalanced forces. (C) equal and opposite reactions. (D) objects in motion.
[A]:
A