A digital signature verifies correctly, but the receiver wants to know whether the message is new. What is the best conclusion?

### Why this is right A valid signature can be attached to a message that was signed earlier. The signature supports authenticity and integrity, but it does not by itself distinguish a new message from a replay. ### The concept Freshness is a separate property from signature validity. A receiver needs some way to assess whether a message is current, because a captured signed message may be sent again. The course specifically warns that a signature alone does not establish that a message is new. ### The other options - **B. Verification proves the message was created moments ago**: a signature contains no such freshness proof by itself. - **C. Verification guarantees the message is confidential**: signatures do not conceal content. - **D. Verification proves that every Certificate Authority trusts the message**: trust depends on accepted authorities and appropriate certificate details. ### Remember A valid signature can still be replayed.