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: Some pea plants always have peas with smooth skin. Other pea plants always have peas with wrinkled skin. How can a student best predict which kind of pea will grow from a seed that is planted?  
 (A) by checking the amount of water in the soil (B) by checking how often the pea plant receives sunlight (C) by checking how much space the plant will have to grow (D) by checking the type of peas growing on the parent plants

A: D
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Q: On a field trip, a student holds a frog and reports that it has slippery skin. This is an example of  
 (A) a measurement (B) a prediction (C) an explanation (D) an observation

A: D
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Q: What is a way of improving air quality?  
 (A) driving large cars (B) building more factories (C) burning wood in the fireplace (D) using solar energy to produce electricity

A:
D
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