"A professor wants to assess students' knowledge of material taught through lectures. However, the professor asks questions that were not discussed during class lectures. This may result in problems with validity."

content

Explanation:

Based on the information provided within the question it can be said that this may result in problems with content validity. That is because content validity refers to how well something measures the behavior or results for which it was intended. Therefore since the professor wants to assess students' knowledge of material taught through lectures he cannot do so by asking questions that were never in the lectures to begin with.

money is the anwser i think