SBI Clerk Exam 11 Jul 2021 Shift 1 Solved Paper

In this question, a sentence has been divided into four parts (A), (B), (C) and (D). Read the sentence to find out whether there is any grammatical error in it. The error if any, will be in one part of the sentence. Mark that part as your answer. If there is no error, the answer is ‘No error’. Ignore the error of punctuation if any.
One of my (A)/ best friends are (B)/ planning to start (C)/ a new venture (D)/ No error (E)