Final answer:
A mismatch, option c, occurs when the NSN of the property received differs from the NSN on the shipping/receiving document.
Step-by-step explanation:
The NSN is an important identification number used in shipping and receiving processes. When the NSN of the property received differs from the NSN on the shipping/receiving document, it is referred to as a mismatch.
A mismatch occurs when the item received does not match the item that was expected based on the NSN recorded on the shipping/receiving document. This can happen due to various reasons such as clerical errors, incorrect labeling, or incorrect scanning of the NSN.
For example, if a shipment of computer monitors is expected based on the NSN, but when received, it turns out to be a shipment of keyboards, it would be considered a mismatch.