How does an RODC maintain an updated DNS database?

The correct answer highlights that when needed, the Read-Only Domain Controller (RODC) requests a single-record replication from another DNS server to keep its DNS database updated. This method allows the RODC to ensure it has the most current information without needing to replicate the entire database from a writable Domain Controller, which enhances both efficiency and security.

In a network with RODCs, changes or updates to DNS records generally originate from writable Domain Controllers. The RODC does not have the capability to make changes to DNS records on its own, which is why it relies on single-record replication. When a particular DNS record is needed or requested, the RODC can initiate a request to the appropriate writable server to receive the specific record update. This targeted approach minimizes the data transfer required and reduces the strain on the network.

Other answer choices do not correctly describe how an RODC maintains its DNS records. Manually updating records based on user requests would be inefficient and contrary to the RODC's design. Querying multiple servers for updates is not an optimal approach and could lead to unnecessary complexity. Finally, storing static DNS records independently does not align with the RODC's purpose, as it is meant to rely on the writable Domain Controllers