Sentence Improvement - Verbal and Reasoning

Directions to SolveIn questions given below, a part of the sentence isitalicised and underlined. Below are given alternatives to the italicised part which may improve the sentence. Choose the correct alternative. In case no improvement is needed, option 'D' is the answer.
Q1:

have lived in Delhi since I was four.

A am living

B lived

C had lived

D No improvement

ANS:D - No improvement

No answer description is available.