The Reason That Paralogous Genes Can Diverge from Each Other

Multiple Choice

The reason that paralogous genes can diverge from each other within the same gene pool, whereas orthologous genes diverge only after gene pools are isolated from each other, is that ________.

A) having multiple copies of genes is essential for the occurrence of sympatric speciation in the wild
B) paralogous genes can occur only in diploid species, thus they are absent from most prokaryotes
C) polyploidy is a necessary precondition for the occurrence of sympatric speciation in the wild
D) having an extra copy of a gene permits modifications to the copy without loss of the original gene product