I used to do this to put in at least one or two softball questions. It helped to weed out who was paying attention and helped when deciding if someone should get a C or C+.
Recall the Master Method and its three parameters a,b,d. Which of the following is the best interpretation of b^d, in the context of divide-and-conquer algorithms?
Alternatively, the problem might be questions that ask for the state of an algorithm at some point, when the algorithm can be correctly implemented in different ways and one is expected to recall/go back and check the exact implementation used.