Final answer:
The most likely cause of delay on an Ethernet CSMA/CD network with low throughput is collisions. Collisions occur when two or more devices transmit data simultaneously and result in delays and retransmission of data, leading to lower throughput.
Step-by-step explanation:
The most likely cause of delay on an Ethernet CSMA/CD network with low throughput is a) Collisions. In a CSMA/CD network, multiple devices share the same transmission medium and collisions can occur when two or more devices transmit data simultaneously. Collisions lead to delays and retransmission of data, resulting in lower throughput.
When a collision occurs, the devices involved in the collision detect the collision and back off for a random amount of time before attempting to retransmit their data. This backoff and retransmission process introduces delays and reduces the overall efficiency of the network.
To mitigate collisions and improve throughput, techniques such as using switches instead of hubs, implementing full-duplex connections, or segmenting the network into multiple collision domains can be employed.