Exam JN0-104 topic 1 question 6 discussion

The correct answer is C. Explanation: When you load the factory-default configuration on a Junos device, you must configure a root password before the commit command will succeed. This is a security measure to ensure that unauthorized users cannot gain access to the device. Option A, "An IPv4 address must be configured on the fxp0 or em0 interface," is not required for the commit command to succeed after loading the factory-default configuration. Option B, "A hostname must be configured," is not required for the commit command to succeed after loading the factory-default configuration. However, it is a best practice to configure a hostname for easier identification of the device. Option D, "An IPv4 default route must be configured," is not required for the commit command to succeed after loading the factory-default configuration. However, if you want the device to be able to communicate with other devices on the network, you will need to configure an IP address and default route.

Ref: Root Password | Junos OS | Juniper Networks “Root Password … When the device is powered on for the first time, it is ready to be configured. Initially, you log in as the user root with no password. You must configure a plain-text password for the root-level user (whose username is root) the first time you modify and commit the configuration. …” Answer: C