I'll give you a question, please answer with step-by-step reasoning process. He liked to write every address out on an index card, then he would sort and store them in his what?
Options:
- office supply store
- library
- address book
- oral report
- card catalogue

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
The organized collection of cards is called card catalogue. He liked to write every address out on an index card, the he would sort and store them in his card catalogue.
The answer: card catalogue.