There's one type of CR question, 'structure'/'describe the role' questions, which will ask you directly about the premise(s) and conclusion of the argument.
It's also useful on other types of CR problem, because understanding an argument is synonymous with understanding the conclusion and premises. In order to get the right answer, for any problem type, you need to know what the argument is saying, and for that, you really only need to know two things:
- What is the author arguing? (That's the conclusion.)
- Why does the author think that his or her point is correct? (That's the premise(s)).
On problem types other than describe the role problems, you don't need to be able to label the exact sentence that contains the conclusion. But if you don't know what it is, there's no reliable way to tell whether an answer is right or not.