Assertion $(A) -$ Flowering plants have developed many outbreeding devices to discourage self-pollination and to encourage cross-pollination.
Reason $(R) -$ Continued self-pollination results in inbreeding depression.

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