Given below are two statements: One labelled as Assertion $A$ and the other labelled as Reason $R$:
Assertion $A$: In gymnosperms,the pollen grains are released from the microsporangium and carried by air currents.
Reason $R$: Air currents carry the pollen grains to the mouth of the archegonia where the male gametes are discharged and pollen tube is not formed.
In the light of the above statements,choose the correct answer from the options given below:

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