Which of the following statements regarding e-commerce is TRUE?

• A. All of the above
• B. Digital signatures function to authenticate e-commerce transactions.
• C. E-commerce entities must make sure that they can determine with whom they communicate.
• D. Non-repudiation is obtained through digital signatures, confirmation services, and timestamps.

Answer: (A)

In e-commerce, ensuring trust hinges on authentication, data integrity, and non-repudiation. Digital signatures provide authentication of the sender and guarantee that the message hasn’t been altered, which is why they function to authenticate e-commerce transactions. It’s also essential to know exactly who you’re communicating with, so mechanisms like digital certificates and PKI are used to verify the counterpart’s identity, preventing impersonation. Non-repudiation means the signer cannot later deny having sent a message; digital signatures contribute to this, and combining them with confirmation services (receipts) and timestamps strengthens it by proving when the signature was created and that the communication occurred. When these elements are all recognizing their roles, every statement is correct, so “all of the above” is the best answer.