Decrypting an ElGamal message requires:

Select one:

a$.$ Both the public and private keys, with specific computations performed by the owner.

b$.$ Access to a pre$-$shared secret passphrase used alongside the public key.

c$.$ Only the public key, allowing anyone to decrypt and read the message.

d$.$ Brute$-$force attacking all possible key combinations until the message is deciphered.