Fill in the blanks with the correct modal
There are plenty of fruits in the fridge. You _____ buy any.

needn't

The correct answer is OPTION 2 -needn't

• The sentence means it’s not necessary to buy fruits because there are already plenty.

• "Needn't" expresses lack of necessity, which fits best.

• mustn't = not allowed (too strict)

•  shouldn't = not advisable (more of a warning)

•  must = necessary (opposite meaning)

 So, the correct sentence is:
"There are plenty of fruits in the fridge. You needn't buy any."