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: A scientist is searching for areas where new solar systems might form. What feature is the scientist looking for?  
 (A) a star similar to our Sun (B) a cloud of dust and gas (C) an oxygen-rich atmosphere (D) a gravitational acceleration of 9.8 m/sec2

A: B
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Q: Your community is planning to build a new sanitary landfill. In locating the landfill, which is the most important environmental consideration?  
 (A) the cost of the land (B) the location of the groundwater (C) the proximity to an industrial park (D) the accessibility to a major highway

A: B
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Q: An increase in which ecosystem factor could cause a population decline in a bird species?  
 (A) emigration (B) immigration (C) number of births (D) amount of food

A:
A
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