Statement $P$: $Salmonella$ $typhi$ are rod-shaped.
Statement $Q$: The incubation period of the bacteria is $1-3$ weeks.

• A
  Both Statement $P$ and Statement $Q$ are correct.
• B
  Both Statement $P$ and Statement $Q$ are incorrect.
• C
  Statement $P$ is correct and Statement $Q$ is incorrect.
• D
  Statement $P$ is incorrect and Statement $Q$ is correct.