Answer: Option (d) is the correct answer.
Step-by-step explanation:
Kinetic energy is defined as the energy obtained by an object due to its motion.
It is known that in a gas, particles move rapidly from one place to another. Hence, molecules of a gas will have high kinetic energy.
So, when there is decrease in kinetic energy of particles of a gas then the particles will come closer to each other and force of attraction between them increases resulting into liquid form.
Thus, we can conclude that the statement they move more slowly, causing the forces of attraction holding them together to increase, resulting in a liquid best explains what happens when the kinetic energy of particles in a gas state decreases.