Which of the following describes the purpose of CSMA/CD?

The purpose of CSMA/CD, or Carrier Sense Multiple Access with Collision Detection, is primarily focused on managing how multiple devices share a communication line. In a network where multiple devices communicate over a shared medium, the likelihood of collisions—situations where two devices attempt to send data simultaneously—can significantly impact overall network performance.

CSMA/CD works by first requiring a device to listen to the network to ensure that the communication line is free (carrier sense). If the line is in use, the device will wait until it becomes available. If two devices transmit data simultaneously and a collision occurs, the CSMA/CD protocol helps detect this collision. Once detected, the involved devices cease their transmission, wait for a random amount of time, and then attempt to transmit again. This process helps to regulate access to the shared communication medium and minimizes data packet loss due to collisions, thereby improving the overall efficiency of the network.

The other options do not accurately reflect the function of CSMA/CD. For example, while it does not eliminate all collisions, it manages the occurrence of them. It does not have any direct effect on data security or specifically enhance wireless communication, which falls under different networking protocols and technologies.