Urgent priority is enabled on the directory number configuration page. This allows the call to be routed at once to the fully qualified DN without any necessity to wait for inter-digit-timeout. If the Urgent Priority checkbox is disabled and you have overlap patterns configured, then CUCM waits for the user to dial further digits.
The other options are incorrect because:
Route partitions are used to group route patterns and route lists.
Transformation patterns are used to convert dialed digits into a different format.
CTI ports are used to connect Cisco Unified Communications Manager to third-party applications.
https://www.cisco.com/c/en/us/support/docs/unified-communications/unified-communications-manager-callmanager/200477-Urgent-Priority-Configuration-on-Directo.html

The call flow for a Mobile and Remote Access registered endpoint to central call control is as follows:
The endpoint registers with the Expressway-C.
The Expressway-C forwards the registration request to the Expressway-E.
The Expressway-E forwards the registration request to the Cisco UCM.
The Cisco UCM registers the endpoint.
When the endpoint places a call, the call flow is as follows:
The endpoint sends the call request to the Expressway-C.
The Expressway-C forwards the call request to the Expressway-E.
The Expressway-E forwards the call request to the Cisco UCM.
The Cisco UCM places the call.
The Expressway-C and Expressway-E are used to provide secure access to the Cisco UCM for endpoints that are not located on the corporate network. The Expressway-C is located on the corporate network, and the Expressway-E is located in the DMZ.