Final answer:
A certificate of stock is not a negotiable instrument because it lacks the requirement of being in writing and signed by the maker or drawer.
Step-by-step explanation:
A certificate of stock is not a negotiable instrument because it lacks the requirement of A. The instrument must be in writing and signed by the maker or drawer. A certificate of stock is a document that represents ownership in a company. While it can be transferred to another person, it does not meet the criteria of a negotiable instrument as defined by the Uniform Commercial Code (UCC).