Which technology can rate-limit the number of tunnels on a DMVPN hub when system utilization is above a specified percentage?

Which technology can rate-limit the number of tunnels on a DMVPN hub when system
utilization is above a specified percentage?

A.
NHRP Event Publisher

B.
interface state control

C.
CAC

D.
NHRP Authentication

E.
ip nhrp connect