Question

Fill the blank with an appropriate modal that denotes a conclusion:

You ____ be mad to do this.

• A. can
• B. must
• C. should
• D. could

Answer 1

The correct option is B must

The option B is correct. Must is used to denote conclusion to be the most logical or rational interpretation of the situation. While can, could be is used in terms expressing ability/lack of ability. Should is used to denote polite suggestion or advice.

Thus the sentence would become:

You must be mad to do this.