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).
He has not been attending English classes since one month.
He has not been attending
English classes
since one month
No error.
Correct answer is C
since the last one month