I am struggling to understand why A is correct. In the final paragraph, the author recommends action "such as replacing fossil-fuel energy". This action would mitigate the temperature rise problem. This must be the "course of action" that the question refers to. Answer choice A offers a solution to "determine whether more costly measures are warranted", that is to learn more about whether action to combat the problem is necessary. This is not what the passage offers. I see that it matches other important information from the passage, such as action under uncertainty, but this difference I have described seems drastic enough for A to be wrong.

Furthermore, B solves this. In B, action to combat the problem is suggested. It also describes action under uncertainty.

Thank you!

#help