Valve is a device for controlling the passage of fluid or air through a pipe, duct, etc., especially an automatic device allowing movement in one direction only. Billy turned off the water by using the diaphragm. A diaphragm is a type of Valve.
This justifies what answer for what question? Q & A: 
user
Billy turned off the water by using the diaphragm. A diaphragm is a type is what?
Options:
- drugstore
- human
- bivalve
- valve
- gas pump
valve
assistant