Assertion $(A)$: In algae,an embryo is formed from the zygote after fertilization.
Reason $(R)$: Algae reproduce sexually through conjugation.

• A
  $A$ and $R$ are true,and $R$ is the correct explanation of $A$.
• B
  $A$ 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.