请教GWD2-2

man855112

Hunter:Hunters alone are blamed for the decline in Greenrock National Forest
’s deer population over the past ten years.Yet clearly, black bears have also played an important role in this decline.In the past ten years, the forest’s protected black bear population has risen sharply, and examination of black bears found dead in the forest during the deer hunting season showed that a number of them had recently fed on deer.
In the hunter’s argument, the boldface portion plays which of the following roles?

A.It is the main conclusion of the argument.

B.It is an objection that has been raised against the main conclusion of the argument.

C.It is a judgment that the argument opposes.

D.It is a finding that the argument seeks to explain.

E.It provides evidence in support of the main conclusion of the argument.

答案是A,那为什么D不对？黑体字后面不就是去解释这一论断的吗？