You are a network technician at Certpaper.com. Which description is correct when you have generated RSA keys on your Cisco router to prepare for secure device management？（）

A、You must then specify the general-purpose key size used for authentication with the crypto key generaters a general-keys modulus command.

B、You must then zeroize the keys to reset secure shell before configuring other parameters.

C、All vty ports are automatically enabled for SSH to provide secure management.

D、The SSH protocol is automatically enabled.