Read the sentence below to find out whether there is any grammatical error in it. The error, if any, will be in one part of the sentence. Choose the option with that part as your answer. If there is no error, choose 'D' as your answer. (Ignore the errors of punctuation, if any).
They have been very close friends until they quarreled.
They have been
very close friends
until they quarrelled.
No error.
Correct answer is A
They had been