Statement $A$: $A$ genus includes more than one species.
Reason $R$: An extinct human species is $Homo\, erectus$.
Which option is correct for Statement $A$ and Reason $R$?

• A
  $A$ and $R$ are both true and $R$ is the correct explanation of $A$.
• B
  $A$ is false and $R$ is true.
• C
  $A$ is true and $R$ is false.
• D
  $A$ and $R$ are both true but $R$ is not the correct explanation of $A$.