Certified Ethical Hacker (CEH v11) — Question 326

Bob, your senior colleague, has sent you a mail regarding a deal with one of the clients. You are requested to accept the offer and you oblige. After 2 days, Bab denies that he had ever sent a mail. What do you want to ``know`` to prove yourself that it was Bob who had send a mail?

Answer options

• A. Non-Repudiation
• B. Integrity
• C. Authentication
• D. Confidentiality

Correct answer: A

Explanation

Non-repudiation ensures that a sender cannot deny having sent a message, which is crucial in this scenario to prove that Bob sent the email. Integrity relates to the accuracy of the message content, while authentication verifies the identity of the sender, neither of which directly addresses Bob's denial. Confidentiality refers to keeping the information private, which is not relevant to proving who sent the email.