Correct option is C
The correct substitution of the bracketed words is (c) No sooner did we arrive.
Explanation: The sentence uses the negative adverb “No sooner”, which requires inversion (helping verb before the subject) in formal structures.
The correct helping verb is “did” and the main verb must be in base form (“arrive”, not “arrived”).
Grammatical rule used:
Negative adverbial phrases like “No sooner… than”, “Hardly… when”, require inversion with did/had and base verb.
Example:
No sooner did she enter the room than everyone applauded.
Information Booster:
“No sooner” is always followed by than, not “when”.
Options (b) "No sooner had we arrive" and (d) "No sooner than we arrived" are also incorrect.
In (b), "arrive" should be in the past participle form as "arrived" after "had."
In (d), the phrase "No sooner than we arrived" does not properly use the "No sooner... than..." structure.