Call into questions means that you are supposed to attack an argument. One might also call this a weaken-question.

Raising a question, on the other hand, is simply asking a question.

A great way to get started with the GMAT is to familiarize yourself with the different question types. That process includes knowing all the words in the questions stem and knowing what you are asked to do. Sometimes this may be a little harder than it sounds.

Example:

If the statements above are true, which of the following is best supported? This is an inference question.

Which of the following statements, if true, best supports the information given above? This is a strengthen question.