Pick the correct sentence :-

The statement in option A is incorrect because it combines the present perfect tense ("have passed") with a specific past time reference ("last year"). The present perfect tense is used to indicate actions that occurred at an indefinite time in the past, not with a specific time reference like "last year." Therefore, the use of "have passed" in this sentence is incorrect.

The sentence in option B is incorrect because it uses the present tense ("pass") to describe an action that occurred in the past ("last year"). When referring to a specific past time, the correct verb form to use is the past tense, which is "passed" in this case.

The sentence in option C is incorrect because it combines the present continuous tense ("am passing") with a specific past time reference ("last year"). The present continuous tense is used to describe ongoing actions happening in the present, not in the past. Therefore, using "am passing" in this sentence to refer to an action in the past is incorrect.

The sentence in option D is the correct sentence. It uses the past tense ("passed") to indicate that the action of passing the examination occurred in the past. The time frame "last year" further specifies when the action took place, making this sentence grammatically correct.

The correct option is D.