For this problem assume that Alice wants to send a single message M to Bob. To do so. Alice and Bob can potentially use a number of different approaches and cryptographic technologies, which we will describe using the following terminology: KA KB -1 Sk sk M Plaintext for a single message AB Concatenation of A with B. Assume the receipient can unambigu- ously decompose this back into the original values of A and B. KA Alice's public key Alice's corresponding private key Bob's public key KB Bob's corresponding private key Ек Public-key encryption using RSA with the public key K Signk-1 Public-key signing using RSA with the private half of K. Symmetric cryptography key AES Symmetric-key encryption using AES-256 in CBC mode, with the key sk AES-EMAC Keyed MAC function presented in lecture, using the key Sk PRNG Bit-stream from a cryptographically strong pseudo-random number generator, seeded with Sk IV An Initialization Vector randomly generated for each use SHA SHA-256 hash function You can assume that the public keys have been securely distributed, so Alice and Bob know their correct values. Consider the following properties that Alice and Bob might desire their communication to have: Confidentiality, Integrity, Authentication, and Non-Repudiation. For each of the following possible communication approaches, please determine if it can be done or not (Yes, or No). Please give reason briefly. a) Alice sends Bob the following message, EKA(M || Signk-- (SHA(M))) b) Alice sends Bob the following message, EKR(M || Sign SHA(M))) c) Alice sends Bob the following message, EKA(M), Signk5+ (SHA(M))