Select the most appropriate option to substitute the highlighted segment in the given sentence. If there is no need to substitute it, select ‘No substitution’.
Had you not interfering in my affairs, I would have been in the US now.

Correct option is B

The correct substitution of the highlighted words is (b) Had you not interfered.
Explanation: The sentence is a third conditional sentence referring to a hypothetical situation in the past. "Interfering" is incorrect; the past participle "interfered" should be used.
Grammatical rule used:
In third conditional sentences, we use “Had + subject + V3” for the conditional clause and “would have + V3” for the main clause.
Structure:
Had + subject + V3, subject + would have + V3
Example: Had he studied, he would have passed.
Information Booster: “Had” can be used to invert the subject and verb for a formal conditional structure, eliminating the need for “if”.