HSRP. Known as Hot Stanclby Router Protocol, is a Cisco proprietarv redundancy protocol . As an experienced network administrator, you are required to configure HSRP on a XYZ network. Which TWO of the following wii be available and shared between the routers configured with HSRP? （）(Choose two.)

A. a shared single interface
B. the ability to track serial interfaces
C. UDP-based hello packets
D. the impact of flapping links if timers are too low