Vocabulary for Conclusion Weakening Questions

All of the following mean about the same as call into question EXCEPT:

Well done! You were not fooled by the similarity in meaning between ask and question. Call into question is a phrase, which means that its meaning is different from the meaning of each word in it.  

Weaken means about the same as call into question.

Undermine means about the same as call into question.

Cast doubt means about the same as call into question.