Critical Reasoning

Diseases have always plagued the earth's living
organisms. Scientists believe that huge numbers
of plant and animal diseases have developed
and been eradicated naturally over time.
This ongoing emergence and disappearance of
diseases is ignored by those who blame the
widespread incidence of cancer entirely upon
man's alteration of naturally occurring substances
to, for instance, produce bigger and
better food sources. For example, some claim
that the use of hormones to increase meat
production heightens the risk of cancer in
people who eat meat. People who hold this
view need to accept the fact that even if cancer
was not such a prevalent disease, another
disease would have arisen naturally to take its
place.
Which one of the following identifies a flaw in
the passage's reasoning?
(A) The writer wrongly assumes that the use
of hormones in meat production never
has an effect upon people who eat meat.
(B) The writer ignores the fact that scientists
are developing cures for some types of
cancer.
(C) The writer does not consider the fact that
a number of diseases have not yet been
discovered.
(D) While the writer identifies a group that
believes cancer is caused by man's interference
with natural forms of food production,
he does not identify or recognize
scientists who disagree with this contention.
(E) The author does not acknowledge that
man's alteration of naturally occurring
substances might trigger the emergence
of new diseases.