Concept:The sentence has a misplaced adjective and verb. Swapping them fixes the grammar and meaning.
Explanation:The word at (B) is "gratuitous" (adjective).
The word at (C) is "indulged" (verb).
After "he", we need a verb, but "gratuitous" is an adjective.
Swapping (B) and (C) gives: "he indulged in some gratuitous self-glorification".
Now "indulged" correctly follows "he", and "gratuitous" modifies "self-glorification".
No other rearrangement makes sense.
Answer:Option A (B-C)