Consider a very simple encryption system that uses 4 bit blocks. It simply adds the data block with the key to encrypt the information. Ignore any overflow (e.g. 1100 +0101 is 0001). Assume we want to encrypt the two 4 bit data blocks shown below with the given key. Show the ciphertext that would be generated using the Cipher Block Chaining (CBC) encryption mode. Show the initialization vector you used IF an IV is necessary. I Plaintext 0000 0100 A B AOB 0 0001 0 0 key 0 1 1 1 0 1 1 IV: 1 1 ciphertext blockl: ciphertext block2