Hello! The best answer would be C - Colds because bacteria can reproduce and spread rapidly, which is why a cold sometimes develops fast. As for the others, your body is just adjusting to the weather with A, B is a sexually transmitted disease which is caused from contact with another through sex, D is caused by sweets/certain foods that break down your teeth. I hope I helped you!! Have a great day!!
It would be the first option. Adenine and thymine.
Answer:
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