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

[Q]: The majority of human genes have two or more possible alleles.
[A]: How many possible alleles do the majority of human genes have?


[Q]: The sun and the moon appear to be about the same size in the sky because the moon is smaller in diameter and is closer to earth than the sun.
[A]: Which statement best explains why the Sun and the Moon appear to be about the same size in the sky?


[Q]: It may seem as though burning destroys matter, but the same amount of what, still exists after a campfire as before?
[A]:
It may seem as though burning destroys matter, but the same amount of what, still exists after a campfire as before?