Given a statement, generate a question such that the answer is contained in that statement.
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Question: The softest mineral is used for making writing lead

Answer: What is the softest mineral used to make?


Question: individual nerve cells transmit nerve signals to other cells.

Answer: What transmits nerve signals to other cells?


Question: Cytoplasm refers to all of the cellular material inside the outer membrane.

Answer:
What refers to all of the cellular material inside the outer membrane?