What system consists of vertical pipes in a building that allow fire hoses to be attached to each floor?

The standpipe system is designed specifically for fire protection within a building. It consists of a network of vertical pipes that run through various floors, providing access to firefighters who can attach hoses directly to these pipes in the event of a fire. This system allows for a reliable and effective means of delivering water to multiple floors without the need for firefighters to drag hoses up stairs, which can be both time-consuming and physically demanding.

In comparison, the water supply system is generally a broader term that encompasses all aspects of water delivery for various uses, including potable water for drinking and general use, but it does not focus specifically on fire suppression. The drainage system pertains to the removal of wastewater and stormwater from a building, and it does not play a role in fire emergencies. The sprinkler system is an automatic fire suppression system that releases water when heat is detected but does not provide the same access for fire hoses that the standpipe system does.

Thus, the standpipe system is the correct choice, as it directly relates to providing firefighters with the necessary connections for hose attachment on each floor to combat fires effectively.