Trading procedures dimensions include

The correct answer is: Both A and B.

Trading procedures dimensions include:

• Location dimension: This refers to the location of the trading venue, such as an exchange or over-the-counter (OTC) market.
• Method of matching orders: This refers to the way in which orders are matched, such as through a central order book or through a broker-dealer network.
• Price dimension: This refers to the price at which orders are executed, such as at the best bid or offer price or through a negotiated process.

Other possible dimensions include:

• Time dimension: This refers to the time at which orders are executed, such as during regular trading hours or after hours.
• Participant dimension: This refers to the type of participants that are allowed to trade on the venue, such as institutional investors or retail investors.
• Instrument dimension: This refers to the type of financial instrument that is traded on the venue, such as stocks, bonds, or derivatives.

The specific dimensions that are relevant to a particular trading venue will depend on the type of venue, the products that are traded, and the regulatory environment.