What command is used to copy the SSH public ID key to a remote server?

The command used to copy the SSH public ID key to a remote server is indeed the one that facilitates the secure and seamless transfer of the public key for authentication purposes. This command automates the process of appending the public key to the ~/.ssh/authorized_keys file on the target remote server. This is essential for enabling passwordless SSH login, which enhances security and convenience for users who frequently connect to remote systems.

When using this command, it prompts for the user's password on the remote server to execute the transfer, and once completed, future connections from the local machine to the remote server can occur without needing to enter a password. This can greatly streamline workflows in environments where regular access to multiple servers is required.

The other options are related to SSH but serve different purposes. The ssh-add command is used for adding private keys to the SSH authentication agent, which allows the user to manage multiple identities. The ssh-keygen command is primarily used for generating new key pairs for SSH authentication. The scp command is used for secure copying of files between hosts on a network but does not manage SSH keys.