Which Junos command correctly configures the ge-0/0/0.0 interface to operate only for IS-IS Level 2?

The command that effectively configures the ge-0/0/0.0 interface to operate solely for IS-IS Level 2 is one that focuses on defining the operational status of the interface concerning its involvement in IS-IS routing levels.

The command set protocols isis interface ge-0/0/0.0 level 1 disable specifically indicates that the Level 1 functionality is turned off for that interface. In IS-IS, Level 1 routing is used for intra-area routing, while Level 2 is used for inter-area routing. By disabling Level 1, the interface is effectively being instructed not to participate in Level 1 routing, thus allowing it to operate exclusively in Level 2. This is crucial for controlling routing behavior in larger networks where you want specific interfaces dedicated to inter-area communications.

In contrast, other commands such as enabling Level 2 or configuring Level 1 parameters do not achieve the goal of restricting the interface to only Level 2 functions. These commands would either allow participation in both levels, which does not meet the requirement of isolation to just Level 2, or simply address settings that do not directly ensure that Level 1 is disabled. Therefore, the selected command directly addresses the requirement of allowing operation