Identify the part containing a grammatical or structural error:
The father with his sons are arriving soon.

Correct option is D

Option (d) contains an error.
Detailed explanation of error: The true subject is “The father” (singular). The phrase “with his sons” is a parenthetical/attendant phrase and does not affect the number of the verb. Therefore, the verb must be singular: “ is arriving soon,” not “are arriving soon.”
Grammatical rule used: When a singular subject is followed by an accompanying phrase (e.g., with, along with, together with, as well as, accompanied by), the verb agrees with the main subject, not the accompanying noun.
Example: “The captain, along with his players, is meeting the press.”
Information booster:
· Conjunction and generally makes the subject plural (“A and B are…”), but prepositional/attendant phrases ( with/as well as/together with) do not.