A customer reports slow network speeds.

Comprehensive and Detailed In-Depth Explanation:

A Network Interface Card (NIC) is the hardware responsible for network connectivity. If the NIC is failing or underperforming (e.g., due to a bad driver, hardware fault, or misconfiguration), it can cause slow or unstable network speeds.

Option A (CPU): A failing CPU affects overall system performance but not specifically network speed.

Option C (HDD): A slow hard drive causes application lag, but not poor network performance.

Option D (RAM): Affects multitasking and speed, not network throughput.

CompTIA A+ Core 1 Exam Objective Reference:

Objective 3.5: Given a scenario, troubleshoot problems related to wired and wireless networks.

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