QUESTION 2 Which from the following is describe Output Feedback mode OFB, where is Pj and Pj-1 are plaintext and previous plaintext, and Cj and Cj-1 ciphertext and previous cipher text, K is a key and E encryption function O Cj = E(K, [Cj-1 XOR Pj]) O Cj = E(K, Pj) Cj = Pj_E(K, [Cj-1 XOR Pj-1]) O None of above Public key encryption, assume that the A encrypts a Text uses private key and send to B, which one from the following described the process of encryption O Even if B knows who sent the text it cannot be decrypted 0 It cannot be decrypted at all as no one knows Private key of A A should send his public key with text B knows its from A and it could decrypt using A public key