The exhausted man needed to have rest, he soon fell to what?
Options:
- relax
- sit down
- sleep
- his death
- closing eyes
Step-by-step reasoning process below:

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
Exhausted means loss of all energy. Losing all energy causes sleep. The answer: sleep.