Astronomers have created a mathematical model for determining whether life ... ...

Which one of the following would most weaken the above argument?
(A) Thousands of responsible people, people with reputations in the community to protect, have claimed to have seen UFOs. Statistically, it is virtually impossible for this many people to be mistaken or to be lying.
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Nova Press: Set F - Classification Practice