The film was properly designed and manufactured to meet it's requirement.is the reasoning for what question and answer pair?

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
Q: Though the thin film seemed fragile, for it's intended purpose it was actually nearly what?
Options:
- indestructible
- durable
- undestroyable
- indestructible
- unbreakable
A: indestructible