The requirement that,to be negotiable,an instrument must promise or order payment of a fixed amount of money applies:

A) only to principal.
B) only to interest.
C) to both principal and interest together.
D) neither to principal nor interest.

Fixed Amount

A specified sum that does not vary or change under specified conditions.

Principal

A main party to a transaction, such as the owner of a business or the party who has authorized an agent to act on their behalf.

Interest

The cost of borrowing money, typically expressed as a percentage of the principal, paid by the borrower to the lender for the use of their money.