Each of the following would be categorised as a liability on a central bank's balance sheet, EXCEPT:a.Securitiesb.Goldc.Moneyd.the commercial banks' accounts.

The correct answer is b. Gold.

Here's why:

a. Securities: These are financial instruments that represent an ownership position in a publicly-traded corporation (stock), a creditor relationship with a governmental body or a corporation (bond), or rights to ownership as represented by an option. In the context of a central bank, securities are typically a liability because they represent money that the bank has borrowed and must eventually pay back.

b. Gold: Gold is a physical asset, not a liability. It's something of value that the central bank owns outright, not something it owes.

c. Money: This can be a liability for a central bank because it represents a claim on the bank's assets. When you hold a banknote, you have a claim on a corresponding amount of assets held by the central bank.

d. The commercial banks' accounts: These are definitely a liability for the central bank. When a commercial bank deposits money with the central bank, the central bank owes that money back to the commercial bank.