Which of the following phrases defines the nature of the ‘Hundi’ generally referred to in the sources of the post-Harsha period?

The correct option is A bill of exchange.

Detailed Explanation:
A Hundi is an ancient financial instrument that developed in the Indian subcontinent. It was extensively used during the post-Harsha and medieval periods as a credit instrument for trade and commerce transactions.
It functioned essentially as a bill of exchange, which is a written, unconditional order by one party (the drawer) to another (the drawee) to pay a specified sum of money to a third party (the payee) at a designated time and place.

Key Features and Functions of a Hundi:
• Safe Transit of Funds: Carrying large amounts of physical currency (such as gold or silver coins) over long distances was highly risky due to thieves and highway robbers. Hundis allowed merchants to travel safely and retrieve cash at their destination.
• Credit Facility: Hundis were also used to raise short-term loans, allowing merchants to buy goods on credit and pay later when the Hundi matured.
• Trust-Based Network: The system operated on a network of merchant bankers (known as Sarrafs or Shroffs) who recognized and honored these documents based on mutual trust and reputation.

Why other options are incorrect:
• An advisory issued by the king to his subordinates: These were official decrees, proclamations, or charters, not financial instruments.
• A diary to be maintained for daily accounts: These daily ledgers or account books were known as Bahi-Khata or Rojnamcha.
• An order from the feudal lord to his subordinates: These were administrative or military commands rather than trade-related financial documents.