The correct answers are C. Pickup roller and D. Separation pad.
A pickup roller is a rubber wheel that grabs the paper from the paper tray and feeds it into the printer. A separation pad is a small piece of cork or rubber that prevents more than one sheet of paper from being fed at a time. If the pickup roller or the separation pad is worn out, dirty, or damaged, it can cause the printer to pull multiple sheets of paper instead of a single sheet. This can lead to paper jams, misprints, or wasted paper.
To resolve this issue, a technician should investigate the condition of the pickup roller and the separation pad and replace them if necessary. The technician should also clean the paper tray and make sure the paper is loaded correctly and not stuck together.
A toner cartridge is a component that contains the toner powder used to create the printout on a laser printer.
A tractor feed is a mechanism that uses sprockets to move continuous paper through a dot matrix printer. A duplexer is a device that allows a printer to print on both sides of the paper automatically. A fuser is a part of a laser printer that melts the toner onto the paper using heat and pressure. None of these components are related to the issue of pulling multiple sheets of paper from the paper tray.
Reference: Types of Printers-What You Need to Know for the CompTIA A+ Exams

NFC (Near Field Communication) is a wireless communication technology that is commonly used for contactless payments, mobile payments, and other mobile transactions. It allows two devices to communicate with each other when they are placed in close proximity.
Contactless payments commonly use NFC (Near Field Communication). NFC is a wireless communication technology that allows two devices to communicate with each other when they are in close proximity.
Contactless payments use NFC to enable customers to make payments by simply tapping their contactless card or mobile device on a payment terminal.

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.

RAID 0 is a disk array configuration that splits data across two or more disks without parity or mirroring.
RAID 0 provides the best I/O performance because it allows parallel read and write operations on multiple disks. RAID 0 also provides the most storage capacity possible because it does not use any disk space for redundancy. However, RAID 0 does not provide any fault tolerance and increases the risk of data loss if any disk fails.
References: The Official CompTIA A+ Core 1 Student Guide (Exam 220-1101) eBook, page 252

If a laser printer is producing output with duplicate images (also known as ghost images), it could be due to an issue with the toner drums and rollers. The first step to eliminate the ghost images would be to clean the toner drums and rollers to remove any excess toner that may be causing the issue.
Ghost images are a common issue in laser printers where an image or text from a previous page appears faintly on subsequent pages. The cause of this issue is usually due to toner residue on the drum or rollers, which can be removed by cleaning the toner drums and rollers. References: Study Guide Section 4.6 - Printer technologies