Which of the following are compounds? O H20 and O2, but not CH4
O O2 and CH4, but not H2O
O H20 and CH4, but not O2
O H20, O2, and CH4

O H20 and CH4, but not O2

Explanation:

Compounds consist of multiple elements. O2 is just two oxygen atoms, meaning two atoms from the same element.

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meiosis is the correct answer