When a Gene Has Been Duplicated One or More Times

When a gene has been duplicated one or more times, what are the possible things that can happen to the duplicated gene?

A) The duplicated gene can accumulate favorable mutations and acquire a new function.
B) The duplicated gene can be lost through deletion.
C) The duplicated gene can be rendered nonfunctional by unfavorable mutations.
D) If there are two copies of the gene, both could undergo mutation so that each evolves a more specialized function than the original gene.
E) All of these are correct.