Sentence Improvement - Verbal and Reasoning

Directions to SolveIn questions given below, a part of the sentence isitalicised and underlined. Below are given alternatives to the italicised part which may improve the sentence. Choose the correct alternative. In case no improvement is needed, option 'D' is the answer.
Q1:

Taxpayers are to be conscious of their privileges.

A have to

B need

C ought to

D No improvement

ANS:A - have to

No answer description is available.