Which of the following controls is used to operate the bumper turret?

The bumper turret is a key component in firefighting apparatus, specifically designed to provide quick and efficient application of water or fire suppressant. The discharge pattern control is essential because it allows the operator to adjust the direction and spread of the water stream that the turret delivers. By manipulating this control, the operator can optimize the fire suppression efforts based on the specific circumstances of the incident, such as the type of fire, the surrounding environment, and the positioning of the vehicle.

In contrast, the other controls listed serve different functions. Speed control relates to the operational speed of the vehicle or equipment but does not influence the operation of the turret directly. A pressure gauge provides crucial information about the pressure of the water supply but does not control how the water is discharged. Similarly, temperature control is typically associated with managing engine or equipment temperatures rather than being involved in the operation of the bumper turret. Thus, the discharge pattern control is the correct and most relevant answer for operating the bumper turret effectively.