Critical Reasoning

Thirty years ago, deer and elk in selected parts of
the Rocky Mountains were first discovered with a
condition known as wasting disease. In 1970, two
percent of the deer and elk killed by hunters were
diagnosed with the disease. In 1995, that percentage
had grown to six percent. This increase in the incidence
of the disease proves that wasting disease has
become much more prevalent in the last twenty-five
years.
If true, which one of the following selections most
seriously weakens the author's conclusion?
(A) Wasting disease has not been discovered in
domestic livestock or in moose or bighorn
sheep, which are also found in significant
numbers in the Rocky Mountains.
(B) Wasting disease tends to make deer and elk
lethargic, making them more easily killed by
hunters.
(C) Since it was first reported, wasting disease
has occasionally been diagnosed in deer
outside the Rocky Mountains.
(D) Hunters have grown more reluctant to
cooperate with the authorities in reporting
their deer and elk harvest, because if wasting
disease is diagnosed in their harvest, the meat
will be destroyed.
(E) It is very difficult to diagnose wasting disease
more than twenty-four hours after death, so
many cases of the disease have gone
undiagnosed