Answer:
Mary should answer that more than half of the boxes not be rejected.
Step-by-step explanation:
Probability:
Box has one defective screen = 0.6
Box has three defective screen = 0.4
no. of screens in a box = 8
The box is rejected if both of the inspected screens are defective.
Probability of rejecting a box:

= 0.04286
Only 4.286% of the boxes will be rejected.
Therefore, Mary should answer that more than half of the boxes not be rejected.