Where do you buy ketchup?
Options:
- refrigerator
- kitchen
- fast food restaurant
- grocery store
- refridgerator
Let's think carefully first. Step-by-step reasoning process:

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
Grocery store is a retail shop that primarily sells food, either fresh or preserved. We do buy ketchup from a grocery store. So the final answer is grocery store.