Which of the following settings should be checked to troubleshoot network issues affecting an individual client?

When troubleshooting network issues affecting a specific client, checking the duplex settings is crucial because they directly impact the client's ability to communicate over the network. Duplex settings determine how a network interface card (NIC) communicates – either in half-duplex mode, where data transmission is alternated, or in full-duplex mode, where data can be sent and received simultaneously.

Improper duplex settings can lead to performance issues, such as slow data transfer or intermittent connections. For example, if one device is set to full-duplex while the other is set to half-duplex, it could cause collisions and significantly degrade the connection quality. Addressing the duplex settings can often resolve connectivity issues observed by the individual client.

In contrast, while router configurations, firewall rules, and network segment settings can also affect network performance, they usually have a broader impact on multiple clients rather than just one. Therefore, the duplex settings are the most relevant point of focus when troubleshooting an issue specific to a single client’s network experience.