In this task, you are given a multiple-choice question and you have to pick the correct option. Answer with option indexes (i.e., "A", "B", "C", and "D").
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Question: Which likely increased atmospheric CO2 recently? (A) sustainable fisheries (B) electric cars (C) motorcycles (D) ant populations

Answer: C


Question: A squirrel likely (A) stores food for the summer (B) stores food for upcoming harsh conditions (C) has little need to store food (D) stores food for the spring

Answer: B


Question: The substance that the respiratory system takes in from the air is released by (A) insects (B) birds (C) plants (D) bears

Answer:
C