Choice "C" is correct. To be negotiable, a note must be payable in money and only in money. A note that allows the maker to pay by performing services is not negotiable. UCC 3-104
Choice "b" is incorrect. To be negotiable, an instrument must be payable on demand or at a definite time. If the latest date for payment can be determined from the face of a demand instrument, it is considered to be payable at a definite time even if that latest date can be reached only through an extension clause. UCC 3-109
Choice "a" is incorrect. To be negotiable, an instrument must be payable on demand or at a definite time. If the latest date for payment can be determined from the face of a demand instrument, it is considered to be payable at a definite time even if it includes an acceleration clause. UCC 3-109
Choice "d" is incorrect. An agent, such as a person having a power of attorney, can sign a negotiable instrument on behalf of a principal.
