Answer:
The pressure of gas will increase.
Step-by-step explanation:
The question above is related to "Boyle's Law." According to this law, provided that the temperature and amount of gas are stable, the absolute pressure of gas is inversely proportional to its volume.
In this sense, if the plunger will be pushed in, the volume of the gas will definitely decrease due to lack of space while the pressure will increase because the molecules of the gas are colliding with each other. The greater the collision, the greater the pressure. This explains the answer above.