Which command encrypts all plaintext passwords?

A.
Router# service password-encryption

B.
Router(config)# password-encryption

C.
Router(config)# service password-encryption

D.
Router# password-encryption

Explanation:
Command
The “service password-encryption” command allows you to encrypt all passwords on your
router so they can not be easily guessed from your running-config. This command uses a
very weak encryption because the router has to be very quickly decode the passwords for its
operation.
It is meant to prevent someone from looking over your shoulder and seeing the password,
that is all. This is configured in global configuration mode.