The correct answer to the first question is a) sabotage can be used both as a verb and a noun.
We have to prevent the sabotage of the project (noun).
They sabotage everything we try to do (verb).
The correct answer to the second question is b) Adverbs modify verbs and adjectives.
Please talk quickly, we don't have much time (an adverb modifying a verb).
His clothes were spotlessly clean (an adverb modifying an adjective).