It is a short-term, negotiable, self-liquidating instrument that is used to finance the credit sales of firms.
Commercial bill
Answer (a) Commercial bill
Explanation: The commercial bills are given by the drawer (seller) on the drawee (buyer) for the worth of products conveyed by him. These bills are of 30 days, 60 days, or 90 days due at maturity. The seller usually gets the bill discounted from his respective bank. This way the commercial bill turns into a marketable investment.