Correct Response: C. In indoor rock climbing, when a belayer is not taking in slack, the belayer's brake hand should always hold the rope in the locked position below the belay device with the hand at the belayer's hip to ensure immediately braking if the climber begins to slip or fall. Communication is essential, but the climber, not the belayer, decides when it is safe to climb, once the "belay on" signal is given (A). Maintaining slack at all times or excess slack in the rope (B) is dangerous as it allows momentum to build on a slip or fall before the rope catches the climber. The belayer's position below the climber (D) may assist with supporting the climber's weight but in itself is not enough to brake a fall.
