The correct answer is a.: specific.
This structure (this +adj) requires an adjective and the only adjective is in a., the other options are verbs or nouns and are not correct.
Answer:
Twist Ending.
Explanation:
Since the question is asking about something that is "unexpected" and "resolves the conflict" (like an ending usually does), the logical answer would be Twist Ending.
I think you meant external conflict?
It would be person V.S. person or Person V.S environment