Statement $1$: Creation or destruction of atoms is not possible.
Statement $2$: Under identical conditions of temperature and pressure,the number of atoms/molecules in a given volume of gas is not the same.

• A
  Statement $1$ and Statement $2$ are both true and Statement $2$ is the correct explanation of Statement $1$.
• B
  Statement $1$ and Statement $2$ are both true and Statement $2$ is not the correct explanation of Statement $1$.
• C
  Statement $1$ is true,while Statement $2$ is false.
• D
  Statement $1$ is false,while Statement $2$ is true.