Given a statement, generate a question such that the answer is contained in that statement.
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Question: locusts spread illnesses and destroy crops

Answer: Who spread illnesses and destroy crops?

Question: Cocaine alters neurotransmitters in the brain.

Answer: What alters neurotransmitters in the brain?

Question: Bacteria may spread directly by touching a person's infected limb.

Answer:
Bacteria can spread directly by what?