Which of the following represents the biggest difference between asymmetric and symmetric cryptography?

A. Asymmetric uses a short string of data for encryption, and symmetric uses a long string of data.
B. Asymmetric uses tokens for encryption, and symmetric uses a short string of data.
C. Asymmetric uses random numbers for encryption, and symmetric uses mathematical algorithms.
D. Asymmetric uses two different keys for encryption, and symmetric uses one shared key.