Select the most appropriate option to improve the bold part of the sentence.
I have visited Delhi last year.

Correct option is B

The correct substitution of the highlighted words is (b) visited.
Explanation: A definite past time marker like last year requires the Simple Past tense. Present Perfect ( have visited) is not used with specific past time adverbials (yesterday, in 2010, last week/year). Therefore, I visited Delhi last year is grammatically correct, concise, and idiomatic.
Grammatical rule used:
· Use Simple Past (V2) with completed actions at a definite time in the past: last year, yesterday, in 2005.
· Do not use Present Perfect (have/has + V3) with a definite past time expression.
· Example: I have met him yesterday. ➝ I met him yesterday.
· Info booster: Present Perfect links past action to the present without a definite time ( I have visited Delhi many times). The moment you specify when, switch to Simple Past.