Environmental Activist: "It Will Eventually Prove Counterproductive to Rely on Pesticides

Multiple Choice

Environmental activist: "It will eventually prove counterproductive to rely on pesticides for crop growth. Even if there are short-term gains in crop yields, insects will eventually become resistant to all known forms of pesticides. We will either have to spend billions researching new forms of pesticides or rely on different kinds of crops in the future. It is much better and will ultimately prove cheaper to grow organic products, even if they seem more expensive now."
Which of the following most accurately describes the role played by the part of the passage stating that insects will eventually become resistant to all known forms of pesticides?

A) It is the argument's main conclusion.
B) It is a conclusion made by the argument, but not its only conclusion.
C) It is a phenomenon for which the argument provides an explanation.
D) It is used as direct support for the conclusions of the passage.
E) It is presented as a counterclaim to the main argument and then later rebutted.