If a Pure-Breeding Long-Tail Cat (LL) Is Crossed with a Pure-Breeding

Multiple Choice

If a pure-breeding long-tail cat (LL) is crossed with a pure-breeding cat with no tail (rumpy, ll) , and a cat with a short tail (stumpy) is produced, the simplest explanation is

A) a mutation.
B) an X-linked gene.
C) an incompletely dominant gene.
D) a lethal gene.
E) chromosomal aberration.