The following statement is true regarding atmospheric type vacuum breakers:

Atmospheric type vacuum breakers are specifically designed to protect against backsiphonage, which occurs when the pressure in a distribution system drops and causes a reverse flow of potentially contaminated water back into the safe drinking water supply. Their primary function is to prevent this type of backflow by allowing air to enter the system when a vacuum condition occurs, thus breaking the siphon effect.

While they provide effective protection against backsiphonage, they are not suited for situations involving continuous pressure; that is, they should not be used in constant pressure applications. Furthermore, their use is limited in capacity and not intended for high-pressure systems. Therefore, option B correctly identifies their purpose and scope of application in preventing backsiphonage.