Here are the vocabulary words matched with their definitions:
1. Gamboled : LEAPT (A)
2. Glimmeringly : UNSTEADILY (D)
3. Hindrances : HANDICAPS (E)
4. Snaggletooth : IRREGULAR (B)
5. Vigilance : CAUTION (C)
These are the synonyms or the words that matched the definition of the given ones. Hope this helps.
I think the Crusades is the correct answer.
The release of more polluting gases to our environment
