Farmer: My neighbor claims that my pesticides are spreading to her farm ... ...

Farmer: My neighbor claims that my pesticides are spreading to her farm in runoff water, but she is wrong. I use only organic pesticides, and there is no evidence that they harm either people or domestic animals. Furthermore, I am careful to avoid spraying on my neighbor’s land. Which one of the following most accurately describes a reasoning flaw in the farmer’s argument?
(A) It treats lack of evidence that organic pesticides harm people or domestic animals as proof that they cannot do so.
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Oct 2012 LSAT (PT67): Logical Reasoning B