Choose the most suitable option to replace the highlighted part of the sentence:
They returned back to home after the event.

Correct option is C

The correct substitution of the highlighted words is (c) returned home.
Explanation: The verb return already means “go back”, so using returned back is a redundant (double) expression. Also, we generally say “return home” (home acts as an adverb of place here), not “return to home” in standard English. Therefore, “returned home” is the most concise and grammatically correct replacement.
Grammatical rule used:
· Avoid redundancy: return = go back, so returned back is incorrect.
· Use: return home / go home (no “to” before home in this sense).
· Example: After the meeting, they returned home late at night.
· Information booster / exceptions related to the topic:
· “Return to + noun” is correct when the place is a noun: return to the city / return to the office.
· With home, we usually drop “to”: return home, go home, come home.