Topic: Group verb,

Best Answer Explained in Below-:

The sentence "He went to the airport to see ---- his uncle" requires a preposition that fits logically and grammatically. Among the given options—of, after, off, and away—only "off" is appropriate in this context.

The phrase "see off" is a common English idiom meaning to go to the place of departure (like an airport or train station) to say goodbye to someone who is leaving. When someone is "seeing off" another person, they typically accompany them to ensure a proper farewell, making "off" the most fitting choice here.

In contrast, the other options do not work well in this context:
- "of" doesn’t convey a meaningful relationship in this sentence structure.
- "after" suggests following someone rather than saying goodbye.
- "away" does not have a direct connection to the act of departing or saying farewell at the airport.

Thus, "see off" captures the intended action of going to the airport specifically to bid farewell to his uncle, making it the correct choice.