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: Energy appears in many forms. What form of energy is lightning?  
 (A) electrical energy (B) mechanical energy (C) magnetic energy (D) sound energy

A: A
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Q: A student plans to grow algal colonies in solutions with different concentrations of liquid fertilizer. Which is a clear and testable hypothesis to guide this investigation?  
 (A) Algae like fertilizer. (B) Fertilizer is good for algae. (C) Fertilizer improves the genetic traits of algae. (D) Algal growth rate increases with fertilizer concentration.

A: D
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Q: Which statement explains why ducklings follow their mother when swimming across a pond?      
 (A) Survival behavior is acquired by interaction with the parent duck. (B) Survival behavior is learned by interacting with their environment. (C) Inherited behavior is genetically obtained through their environment. (D) Inherited behavior is genetically passed on from parents to offspring.

A:
D
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