Which of the following is an asymmetric cipher?

RSA

https://en.wikipedia.org/wiki/RSA_(cryptosystem)

RSA (Rivest–Shamir–Adleman) is a public-key cryptosystem that is widely used for secure data

transmission. It is also one of the oldest. The acronym RSA comes from the surnames of Ron Rivest,

Adi Shamir, and Leonard Adleman, who publicly described the algorithm in 1977. An equivalent

system was developed secretly, in 1973 at GCHQ (the British signals intelligence agency), by the

English mathematician Clifford Cocks. That system was declassified in 1997.

In a public-key cryptosystem, the encryption key is public and distinct from the decryption key, which

is kept secret (private). An RSA user creates and publishes a public key based on two large prime

numbers, along with an auxiliary value. The prime numbers are kept secret. Messages can be

encrypted by anyone, via the public key, but can only be decoded by someone who knows the prime

numbers.

Incorrect answers:

DES - is a symmetric-key algorithm for the encryption of digital data. Although its short key length of

56 bits makes it too insecure for applications, it has been highly influential in the advancement of

cryptography.

RC4 - RSA (Rivest–Shamir–Adleman) is one of the first public-key cryptosystems and is widely used

for secure data transmission (stream cipher).

AES - is a subset of the Rijndael block cipher developed by two Belgian cryptographers, Vincent

Rijmen and Joan Daemen, who submitted a proposal to NIST during the AES selection process.

Rijndael is a family of ciphers with different key and block sizes. For AES, NIST selected three

members of the Rijndael family, each with a block size of 128 bits, but three different key lengths:

128, 192 and 256 bits.