$P$: Lake or sea water does not freeze completely.
$Q$: The latent heat of water is very high.

• A
  Statement $P$ is true and statement $Q$ is false.
• B
  Both statements $P$ and $Q$ are true. Statement $Q$ is the correct explanation of statement $P$.
• C
  Both statements $P$ and $Q$ are false.
• D
  Both statements $P$ and $Q$ are true. Statement $Q$ is not the correct explanation of statement $P$.