Answer
A. Its volume is decreased
Explanation
If we compress a gas (decrease) without changing its temperature, the average kinetic energy of the gas particles remains the same.
At a constant temperature, the kinetic energy of particles remains the same. If the volume is reduced at a constant temperature, then the number of particles in unit volume or area increases. If there is an increased number of particles in the unit area then it increases the frequency of collisions per unit area.
At constant temperature, the smaller the volume of the container, the larger the pressure.
Control group: 50 dogs continuing their normal diet
Experiments group: 50 dogs chosen to eat the new food
Independent variable: dog food
Dependent variable: the dogs’ weight
