One of the following sentences is nonsensical. Which one is it?
Options:
- Sentence A: "it has been rainy for a long time and the river flooded"
- Sentence B: "it has been rainy for a long time and the river dried up"
 Let's be accurate as possible. So think first.

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 river can't dry up during a long rain.
The final answer: Sentence B.