Can yall help me please and tyyyyyyyyy

A mutagen is a chemical compound or form of radiation that causes mutations, which of course means a change in the dna of a cell. So, your answer would be C) an environmental agent that changes DNA.

For example, the wing of a butterfly and the wing of a bird are analogous; the two types of wings share a common function (and therefore both are called wings), but the bird wing and insect wing did not arise from a common original ancestral structure that become modified through evolution into bird wings and butterfly ...