Which type of fire extinguishing method contains standing water in the pipe, and therefore generally does not enable a manual shutdown of systems before discharge?

Which type of fire extinguishing method contains standing water in the
pipe, and therefore generally does not enable a manual shutdown of
systems before discharge?

A.
Dry Pipe

B.
Deluge

C.
Wet pipe

D.
Preaction

Explanation:
The other three are variations on a dry
pipe discharge method with the water not standing in the pipe until a
fire is detected.