Which of the following sentences from the article supports the idea that inventors not succeeding the first time is a good thing?

a
The ROV exercise wasn't a competition, but a self-test of each team's design and maneuvering ability.
b
"I thought we'd come to the pool and everything would work perfectly," said Vivian Kocsis, 12. "It didn't."
c
"A mistake is not the end of the world," said McDonald. "Fixing it builds confidence."
d
Students patiently tackled these problems on-site.

Ithink that it’s mali

Europe needs to build a trump-like wall that will spread across europe making it impossible for migrants to cross they need to spread pig guts all over this wall so the muslims will never consider crossing into europe..you might be asking "can't they just fly over with planes? " well yes they can so we will install thaad missile protections system to shoot down any aircraft that violates europe's air fourth would be to start a fourth reich in germany.. last but not least.. make europe great again!