Refer to the exhibit. The distribution switches serve as the Layer 3 boundary. HSRP preemption is enabled. When the primary switch comes back after a failure, traffic is initially dropped. Which solution must be implemented to improve the design? 

Answer options:

A. Increase the hello timers on both HSRP devices.
B. Use the preempt delay feature on the backup HSRP device.
C. Use the preempt delay feature on the primary HSRP device.
D. Configure a higher mac-refresh interval on both HSRP devices.

C