You are given a science question (hard-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: A wetland habitat can continue to support the birds and fish that live there if people ___.  
 (A) drain the water away (B) flood the highest parts of the land (C) leave the land alone (D) use the land for planting crops

A: C
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Q: The force of an object, with a certain mass accelerating at a certain rate, can be determined by using the equation below. force = mass x acceleration Which object would have the greatest force?  
 (A) a 5-kg object accelerating at 10 m/s^2 (B) a 5-kg object accelerating at 20 m/s^2 (C) a 20-kg object accelerating at 4 m/s^2 (D) a 20-kg object accelerating at 3 m/s^2

A: B
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Q: A morning glory is a type of flowering vine that climbs trees and fences. Which of the following behaviors most helps a morning glory plant climb a fence?  
 (A) stems curling in response to touch (B) stems swelling in response to water (C) flowers opening in response to light (D) roots growing in response to gravity

A:
A
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