In financial markets, which of the following activities is carried out at a stock exchange?

Introduction / Context:
A stock exchange is a key institution in modern financial systems. It is often mentioned in news about share prices, market indices and corporate listings. For competitive exams, you must know the basic function of a stock exchange and what is traded there. This question checks your understanding of what is actually bought and sold on a stock exchange as opposed to ordinary commodity markets.

Given Data / Assumptions:

• The question is about the role of a stock exchange.
• Options distinguish between commodities and securities.
• Stock exchanges are usually associated with financial instruments.
• We assume a standard organised stock market, such as the BSE or NSE in India.

Concept / Approach:
A stock exchange is an organised marketplace where securities such as equity shares, preference shares, debentures, bonds and sometimes derivatives are traded. Companies list their securities on the exchange so that investors can buy and sell them easily. Commodity markets exist separately for trading physical goods like wheat, metals or crude oil, often through commodity exchanges. Prices at stock exchanges are determined by demand and supply for financial securities, not ordinary wholesale or retail trade in physical commodities.

Step-by-Step Solution:
Step 1: Recall that the primary function of a stock exchange is to facilitate trading of financial securities. Step 2: Recognize that commodities such as grains, metals or oil are usually traded on commodity exchanges, not on stock exchanges. Step 3: Examine the options and identify which one mentions securities being bought and sold. Step 4: Select the option that refers to trading in securities such as shares and debentures as the correct activity of a stock exchange.

Verification / Alternative check:
Think of common names like the Bombay Stock Exchange (BSE) or the National Stock Exchange (NSE). News reports always talk about share prices, market capitalization and index movements, which are all related to securities trading. They do not talk about wholesale or retail prices of physical goods being traded there. This everyday observation confirms that securities trading is the defining activity of a stock exchange.

Why Other Options Are Wrong:
Commodities bought and sold at wholesale price: This describes a wholesale commodity market, such as a mandi, not a stock exchange which deals in financial securities.
Commodities bought and sold at retail price: This fits a retail market where final consumers purchase goods, not an organised financial market like a stock exchange.
None of these: This is incorrect because one of the options clearly describes the correct function of a stock exchange, namely buying and selling securities.

Common Pitfalls:
A common mistake is to think that the word “stock” refers to physical stock of goods rather than financial instruments such as stocks or shares. Another pitfall is not distinguishing between commodity exchanges and stock exchanges. Remember that stock exchanges specialise in securities, while commodity markets focus on physical goods or commodity derivatives.

Final Answer:
At a stock exchange, securities such as shares and debentures are bought and sold.