Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Q: When a sperm penetrates the egg, it triggers the egg to complete meiosis.

A: When a sperm penetrates the egg, it triggers the egg to complete what?
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Q: Environmental changes is most responsible for the extinction of most species of plants and animals that have lived on earth.

A: What process is most responsible for the extinction of most species of plants and animals that have lived on Earth?
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Q: Sandblasting a surface exemplifies abrasion form of erosion.

A:
Sandblasting a surface exemplifies what form of erosion?
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