A crimper is a tool that is used to attach connectors to network cables, such as RJ-45 or RJ-11. A technician might need a crimper to create a longer cable for the router access point or to replace a damaged connector.
A Wi-Fi analyzer is a software or hardware tool that can scan and measure the wireless signal strength, interference, channel usage, and security of a Wi-Fi network. A technician might need a Wi-Fi analyzer to find the optimal location and configuration for the router access point to improve the signal coverage for the SOHO client.
Reference
* [CompTIA A+ Core 1 (220-1001) Certification Study Guide], page 77
* [CompTIA A+ Core 1 (220-1001) Certification Study Guide], page 82
* [What is a Crimper?]
* [What is a Wi-Fi Analyzer?]

Explanation
The correct answer is D. Default gateway.
A default gateway is the device that connects a local network to other networks, such as the internet. A default gateway is usually a router or a modem that has an IP address on the same subnet as the local network. A default gateway is necessary for a device to communicate with devices outside its local network.
In this case, the user has a self-configured, static IP address of 192.168.1.20, which belongs to the subnet
192.168.1.0/24 (with a subnet mask of 255.255.255.0). However, the default gateway is set to 192.168.0.1, which belongs to a different subnet (192.168.0.0/24). This means that the user's device cannot reach the default gateway, and therefore cannot connect to the internet.
The technician should edit the default gateway to match the correct subnet of the user's device, such as
192.168.1.1 or 192.168.1.254, depending on the configuration of the network.
Reference: CompTIA A+ Core 1 Sample Questions and Study Guide

Speed is the most important consideration. Striping without parity, also known as RAID 0, is a RAID configuration that splits data across multiple disks without any redundancy. This improves the performance of read and write operations, as multiple disks can work in parallel. However, this also increases the risk of data loss, as any disk failure will result in losing all data on the array. Therefore, striping without parity is suitable for situations where speed is prioritized over reliability. According to the CompTIA Core1 objectives, one of the advantages of RAID 0 is increased speed. A research paper on RAID performance also confirms that RAID 0 has the highest throughput among all RAID levels.

Explanation
The manufacturer's specifications for the components are the best source of information to determine the appropriate power supply for the workstation. The manufacturer's specifications will list the power requirements and recommendations for each component, such as the graphics card, the CPU, the hard drives, and the motherboard. By adding up the power consumption of each component, the technician can estimate the total wattage needed for the workstation. The technician should also consider some extra headroom for future upgrades or peak loads. The technician can then choose a power supply that meets or exceeds the total wattage and has the right connectors and form factor for the workstation.