Question

Fill in the blank with a suitable modal auxiliary:

She doesn't have any money so she ____ pay her bills.

• A. can
• B. can't
• C. couldn't
• D. could

Answer 1

Answer: (B)

can't

Modal Verbs show us the attitude of the speaker to what is being said or done. The term "modal" means expressing mood and mood is a way to express the attitude of the speaker.

The given sentence is firstly set in present tense and secondly according to the meaning of the sentence it expects a mood of impossibility.

Option B is the correct answer because it expresses impossibility or inability in the past.

Whereas option A expresses ability in present;

option C expresses impossibility in past;

Option D expresses something uncertain about what could happen in the past, therefore it is not applicable in the given sentence.