The CD in CSMA/CD refers to the ability of an Ethernet node to do which of the following?

The term "CD" in CSMA/CD stands for "Collision Detection." This aspect of the Carrier Sense Multiple Access with Collision Detection protocol allows an Ethernet node to monitor the network while transmitting data. When a node sends a frame, it also listens for any signals that might indicate a collision—this occurs if two or more nodes transmit simultaneously, causing interference. The ability to detect such collisions is crucial, as it enables the node to take corrective action, typically by stopping its transmission and waiting for a random backoff period before trying to send the data again. This collision detection mechanism helps maintain efficient communication and reduces the likelihood of continuous transmission failures.

In the context of the other choices: while sending data, controlling packet flow, and performing error correction are important network functionalities, these do not specifically relate to the concept of collision detection embodied in CSMA/CD. The protocol is focused on managing access to the network medium and responding to collisions rather than those other activities.