Can someone help me please i’ll give

As the option says, the kinetic energy will decrease.  the volume decreases because  the molecules are slower and collide less. Less molecules make the effective collisions due to which the kinetic energy of molecules is less, so less kinetic energy results in the shrinkage. So decrease in temperature lowers the rate of the reaction and in the volume.

the atomic number will stay the same no matter how many electrons it has, so it doesn’t decrease nor increase. it’ll only change with a different number of protons