For any block cipher, the fact that it is a nonlinear function is crucial to its security.To see this, suppose that we have a linear block cipher EL that encrypts 128-bit blocks of plaintext into 128-bit blocks of ciphertext. Let EL (k, m) denote the encryption of a 128-bit message under a key (the actual bit length of is irrelevant).Thus, EL(k, [m1 "XOR" m2]) = EL(k,m1) "XOR" EL(k,m2) for all 128-bit patterns m1, m2 Describe how, with 128 chosen ciphertexts, an adversary can decrypt any ciphertext without knowledge of the secret key . (A chosen ciphertext means that an adversary has the ability to choose a ciphertext and then obtain its decryption. Here, you have 128 plaintext/ciphertext pairs to work with and you have the ability to chose the value of the ciphertexts.)