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").

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

A: C
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Q: Which of the following would have best aided a vessel at sea in crossing the sea in the 18th century? (A) A radar system (B) An old soothsayer (C) An experienced navigator (D) A crow's nest

A: C
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Q: Taking a fingernail and pressing it to salt will show (A) it is dry (B) it is wet (C) it is malleable (D) it is salty

A:
C
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