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.
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Question: India is in the Northern Hemisphere and Australia is in the Southern Hemisphere. In June, it is summer in India and winter in Australia. What is the main reason the seasons are opposite in the two countries?  
 (A) because Earth is tilted on its axis (B) because the Sun rotates on its axis (C) because Earth revolves around the Sun (D) because of the distance between the countries

Answer: A


Question: When nitrogen-rich runoff from farms enters a nearby farm, it causes abundant growth of algal mat on the pond surface. As a result, underwater plants in the pond begin to die. Identify the limiting factor that is most responsible for causing the underwater plants to die.  
 (A) oxygen (B) sunlight (C) nitrogen (D) carbon dioxide

Answer: B


Question: When compared to the Sun, red dwarf stars are  
 (A) older. (B) cooler. (C) lower density. (D) larger diameter.

Answer:
B