Non-repudiation refers to a method used to guarantee that parties involved in an e-commerce transaction cannot deny their participation.

• A. True
• B. False
• C. Not applicable
• D. Depends

Answer: (A)

Non-repudiation is the ability to prove who participated in a transaction and that the action occurred, so a party cannot credibly deny it later. In e-commerce this is typically achieved through digital signatures tied to the signer’s identity, along with secure logs and timestamps that record the exact action. The signer’s private key creates a signature that anyone can verify with the corresponding public key, providing undeniable evidence of who performed the transaction and when. Because of this verifiable evidence, participants cannot later deny their involvement. So the statement is true. The other options don’t fit because non-repudiation is a defined security service that aims to prevent denial of participation; it isn’t inherently not applicable or dependent in typical implementations.