The algorithm with different encryption key and decryption key is called asymmetric encryption algorithm, also known as public key cryptosystem, which solves the problem of key distribution and transmission of symmetric key algorithm. In asymmetric encryption algorithm, the private key is used for decryption and signature, and the public key is used for encryption and authentication. RSA belongs to asymmetric encryption algorithm, DES, 3DES and RC4 belong to symmetric encryption algorithm. Answer: c