Question

the officer asked the clerk/ whether he has/finished this work
find the error location

Answer 1

It will be The officer asked the clerk whether he had finished his work..

Answer 2

There are errors in the second and third phrases of the sentence structure.

The sentence as a whole is in indirect speech, which means that past tense of verbs should be used and the adjectives being used must refer to objects indirectly.

After correction, the whole sentence turns out to be, ‘The officer asked the clerk whether he had finished that work.’.