Answer
the building of something, typically a large structure.
1. Verb : found .....helping :can be
2.Verb :authenticated ......helping:idk
4Verb.:scampered helping : across
5. devising, constantly
6.purchased, could
7. served, after-before
8. seek, must
9.do, after
10. have, been
11. seeing
12. soaping , before
I'm not 100% sure but I think it is A. Sorry if it is wrong.