Answer:
Volume increases
Step-by-step explanation:
According to Boyle's law, the pressure will increase with the decrease in volume or pressure will decrease with the increase in volume.
If a balloon kept in a room with a lower pressure then its volume will increase because the pressure is directly proportional to the number of gas molecules in the balloon, lower pressure means less collision of air molecules, and more volume will be occupied by the air molecules.
Hence, the volume will increase by lowering the pressure.