Auto Scaling requests are signed with a _________ signature calculated from the request and the user’s private key?

Explanations:

SSL is a protocol for secure communication, not a signature method.

AES-256 is an encryption algorithm, not used for signing requests.

HMAC-SHA1 is a hashing method used to create a signature based on the request and a private key.

X.509 is a standard for public key certificates, not a signing method for requests.