Text: An electronic signature is a method of signing an electronic message that (1) identifies and authenticates a particular person as the source of the electronic message and (2) indicates such person's approval of the information contained in the electronic message.
Entailment: An electronic signature is a method of signing an electronic message which authenticates a particular person as the source of the electronic message.
Contradiction: An electronic signature isn't a method of signing an electronic message that (1) identifies and authenticates a particular person as the source of the electronic message