The RS-232 standard is a common serial communication protocol often used for connecting and controlling various AV devices. It typically employs a DB9 connector, which is illustrated in Option C. The DB9 connector is a 9-pin D-sub connector, widely used in RS-232 connections due to its reliable performance in transmitting serial data.

Here’s an overview of the connector options in the image:

Option A: This is an RJ-45 connector, commonly used for Ethernet networking (data communication), not for RS-232.

Option B: This is a VGA connector, often used for video signals, typically between computers and monitors.

Option C: This is a DB9 (DE-9) connector, which is most commonly associated with RS-232 serial connections.

Option D: This is an XLR connector, generally used for audio signals, especially in professional audio applications.

CTS Technology Specialist Reference

In AV systems integration, RS-232 is frequently employed for control and communication between devices such as projectors, displays, and control processors. According to CTS training materials, the DB9 connector is the most recognized form of connection for RS-232 due to its reliability and ease of integration in various AV systems.