When attempting to send a file to another user securely with GPG, which of the following actions must be done?
A.
Encrypt the file using your public key
B.
Encrypt the file using their public key
C.
Encrypt the file using your private key
D.
Encrypt the file using their private key
E.
Sign the file with your public key
Explanation:
You always use the Public key of the person you want to send the data to to encrypt it, because the data can only be decrypted with the private key.
To authenticate messages you do the opposite, encrypt a hash of the message with your private key, and every one can decrypt it with the public key, thus proving that you signed the message.