What types of members exist on a security exchange?

The correct choice identifies key types of participants that operate within a securities exchange, which are essential to facilitating transactions and maintaining market efficiency.

Commission brokers are acting as intermediaries, executing buy and sell orders for clients. They are critical for ensuring that trades are conducted in accordance with the regulations of the exchange. Registered traders, who are often involved in making trades on behalf of financial institutions or their own accounts, add another layer of market participation by providing liquidity and aiding price discovery. Odd-lot dealers, who specialize in handling odd-lots—those shares that do not constitute a standard unit (usually 100 shares)—serve to accommodate smaller trades which may not meet the threshold of larger transactions but are equally important for overall market activity.

The other options are incomplete or overly restrictive regarding the types of members present on a securities exchange. While registered traders and investment advisors do play roles within financial markets, they do not encompass the full range of member types within a securities exchange. Similarly, stating that only brokers working directly with clients are members ignores the roles of different market participants, including those who trade on their own accounts or under specific arrangements. The mention of shareholders and stockholders pertains more to ownership than to the operational roles within a securities exchange, which is focused