Question $3$

In WiMAX network, the function of Network Access provider $($NAP$)$ element is to $\_\_\_\_\_\_\_\_\_\_\_.$

provide radio access to WiMAX subscribers

provide path between a WiMAX radio access infrastructure to one or more WiMAX Network Service Providers.

provide IP connectivity services to WiMAX subscribers.

provide IP connectivity and WiMAX services to WiMAX subscribers.