a) We have a statistical question here because the population is the set of children's literature readers. We then gather a sample of readers (some subset of the population) and ask what their most favorite genre is of the children's literature category. As expected, we're dealing with a categorical variable and it's also qualitative. Each choice "biography", "science fiction", "fantasy", and "mystery" are categories, names or labels. There is no inherent order to any of these, other than alphabetical order, so we consider this a nominal variable.
b) J.K. Rowling is best known for writing the Harry Potter series, which belongs in the fantasy section. There is no randomness to this answer and it's a single answer that does not change. You could have some people say that perhaps the genre is action/adventure, though I think "fantasy" is the better fit. We don't have a statistical question because we don't need to gather a sample and conduct a survey to answer this. Part (a) can vary randomly, which is one way to help see that part (a) is a statistical question; however, part (b) is fixed and constant.
