What is the Purpose of a Digital Signature?

The correct answer is A. It serves the purpose of non-repudiation.

Here's why:

Non-repudiation: A digital signature ensures that the sender of a message or document cannot deny having sent it. It provides proof of origin and integrity. * Not a Scanned Signature: Digital signatures are not simply scanned copies of physical signatures. They are based on complex cryptographic algorithms.* Asymmetric Encryption: Digital signatures primarily use asymmetric encryption, involving a public and private key pair. * Availability: Digital signatures contribute to data integrity and authentication but do not directly guarantee data availability.

In essence, digital signatures act like a tamper-proof seal for digital information, ensuring its authenticity and origin.