A characteristic of a digital signature is that it:
A characteristic of a digital signature is that it:
A digital signature is unique to the message because it is created using a cryptographic algorithm that takes the content of the message and the sender's private key into account. This makes it highly improbable for two different messages to generate the same digital signature, ensuring the authenticity and integrity of the message.
B. is unique to the message.
This uniqueness is achieved through the use of cryptographic algorithms that generate a signature based on the content of the message and the sender's private key, making it mathematically improbable for two different messages to produce the same signature. Option D, "is validated when data are changed," refers more to the property of digital signatures being able to detect alterations to the signed data rather than a characteristic of the signature itself.