Task: Question Answering
Input (English): Question: Each shelf of a bookcase contains 24 books. If the librarian took out 40 books and rearranged the remaining books so that all shelves but the last one contained 20 books and the last shelf contained 20 books, how many shelves does the bookcase have?

 Option A: A

 Option B: B

 Option C: C

 Option D: D

 Option E: E
Output (English): Option E