Which ip nhrp registration command allows a spoke with a dynamic IP to send traffic over the DMVPN tunnel?

The ip nhrp registration no-unique command allows a spoke router with a dynamic IP address to register with the DMVPN hub. By default, NHRP requires a unique mapping between a spoke's tunnel IP and its public IP. When a spoke has a dynamic public IP, this mapping changes, and the hub might reject subsequent registrations if it still holds the old, now-invalid mapping. no-unique tells the hub to accept registrations even if the public IP changes, effectively overwriting previous entries for the same tunnel IP. no-registration would prevent the spoke from registering at all. dynamic is not a valid NHRP registration option. ignore is also not a valid NHRP registration option; it's typically used in other contexts like routing protocol neighbor statements.