During taxi, if the brake pressure is low, which indication might appear?

The indication that would appear during taxi if the brake pressure is low is the brake pressure warning light. This light serves as a critical alert to the flight crew, indicating that the hydraulic pressure in the braking system has dropped below safe operational levels. Maintaining adequate brake pressure is essential for effective stopping power and control during taxiing, takeoff, and landing.

The brake pressure warning light is specifically designed to enhance safety by notifying the pilots about potential issues within the braking system. When the pressure drops too low, it could lead to inefficient brake performance, thereby compromising the aircraft's control.

The other options do not correspond with the situation of low brake pressure during taxi. For instance, the low-speed warning would typically be related to the aircraft being below a minimum airspeed for safe operation, not brake pressure concerns. The brake temperature indicator shows temperature levels of the brake system rather than pressure. Similarly, the landing gear warning relates to the configuration of the landing gear and does not pertain to brake pressure at all. Thus, the presence of the brake pressure warning light serves as a direct and relevant indicator of the issue at hand.