Which three characteristics of the Single Tier and the Dual Tier Headend Architectures for DMVPN designs are true? (Choose three.)

Neither architecture is mandated by dual cloud topology - the choice between Single and Dual Tier is driven by scalability and functional separation requirements, not cloud count.

Single Tier places one headend router per DMVPN cloud that handles all functions, making it the simplest topology for smaller deployments.

Single Tier is not required for dual cloud topologies - Dual Tier can equally support dual cloud designs including spoke-to-spoke tunnels.

Dual Tier is not defined by simply having two routers per cloud - its defining trait is the functional separation of GRE and IPsec endpoints, and a Single Tier headend can also have multiple routers for redundancy.

In Single Tier, the GRE tunnel endpoint and IPsec encryption endpoint are collocated on the same headend router, so both NHRP registration and crypto processing occur on one device.

In Dual Tier, the front-end router terminates GRE tunnels and processes NHRP while a separate back-end router handles IPsec encryption, distributing the processing load across two functional layers.