Assertion $(A)$: The temperature of a gas is a result of the kinetic energy of its molecules.
Reason $(R)$: Due to kinetic energy,the molecules collide with each other to produce thermal energy.

• A
  Both $(A)$ and $(R)$ are true and $(R)$ is the correct explanation of $(A)$
• B
  Both $(A)$ and $(R)$ are true but $(R)$ is not the correct explanation of $(A)$
• C
  $(A)$ is true but $(R)$ is false
• D
  $(A)$ is false but $(R)$ is true