Consider a simple system with 8-bit block size. Assume the encryption (and decryption) to be a simple XOR of the key with the input. In other words, to encrypt x with k we simply perform xk giving y. Similarly, to decrypt y, we perform yk giving x.

You are given the following 16-bit input F5C6 in hexadecimal. You are provided IV as 8C in hexadecimal. The key to be used (where appropriate) is 49 in hexadecimal. Compute the encrypted output with the following methods. Express your final answer, for each of them, as 4 hexadecimal characters so it is easy to read.

A. (Points 5) Using ECB

B. (Points 5) Using CBC

C. (Points 5) Using OFB

D. (Points 5) Using CFB