Critical Reasoning: Conclusion Weakening Questions

To which Critical Reasoning question type does the following question stem belong?

"Which of the following, if true, undermines the author's conclusion?"

Good!

The word undermines has approximately the same meaning as weaken.

Incorrect. The question stem of Assumption questions usually includes the word assumption or a similar word.

Incorrect. The question stem of Conclusion Strengthening questions usually includes the word strengthen or support.