Final answer:
When the volume of the box is suddenly increased, the most likely effect on the pressure of the gases inside is pressure decreases.
Step-by-step explanation:
When the volume of the box is suddenly increased, the most likely effect on the pressure of the gases inside is B. Pressure decreases. When the volume of the box is suddenly increased, the most likely effect on the pressure of the gases inside is pressure decreases.
This is because according to Boyle's Law, which states that the pressure and volume of a gas are inversely proportional at constant temperature, an increase in volume will result in a decrease in pressure. As a result, the pressure of the gases inside the box will decrease.