In the following questions, a sentence is written in four different ways. Choose the option which gives the most effective and grammatically correct sentence. Pay attention to grammar, word choice and sentence construction.
He is sure to receive his pay. It is due to him. Why then does he worry?

A. Why does he worry, till he is sure to receive his pay due to him?

B. Why should he worry as the pay due to him is sure to be received?

C. Why does he worry as he should be sure to receive the pay due to him?

D. None of the above sentences is correct.

Please do not use chat terms. Example: avoid using "grt" instead of "great".