Answer:
b. As particles travel in straight lines, their paths sometimes meet, and then they bounce apart with no gain or loss of energy.
Step-by-step explanation:
Kinetic - molecular theory -
According to this theory , gas is considered to be as a large number of very small particles , which moves randomly , and due to this randomness collisions occurs , as the particles collide with each other and the wall of the container .
During these collisions , there is no loss or gain of energy , there is only transfer of energy .