Fill in the gap to complete the sentence: I shall ___

Fill in the gap to complete the sentence: I shall ____ the sum before the teacher comes.

A have done

B done

C be going

D do

Correct Answer: Option A

Future perfect tense -এর গঠন, subject + shall have + verb -এর p.p. form + ob. + ext. সুতরাং have done বসে ।