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: What will air usually do when heated up beyond a certain point? (A) it will fall (B) it will remain (C) it will ascend (D) it will die

Answer: C


Question: What is a source of oxygen through photosynthesis? (A) lakes (B) car engines (C) sunflowers (D) people

Answer: C


Question: In order to play with a beach ball, you need to fill it with (A) with ice (B) with water (C) a gaseous substance (D) with oil

Answer:
C