A managed switch is a network device that can be configured to create VLANs (Virtual Local Area Networks), which are logical segments of a network that isolate traffic based on criteria such as function, security, or quality of service. A VLAN can be used to isolate voice traffic on the network, which can improve the performance and security of voice over IP (VoIP) applications. A network tap, a hub, and a DSL filter are not capable of creating VLANs.
Reference: [CompTIA A+ Core 1 (220-1101) Certification Study Guide], page 32.

Every computer has a CMOS battery and when you remove that battery, your computer will work almost the same as before. The only difference is you won't be able to save any settings in the BIOS, which includes the date and time. If your PC is not booting after removing CMOS, you need to make sure that you have your CPU and RAM connected because it's not possible for your system to boot without those.. Your motherboard and computer will be able to boot just fine even without a CMOS battery present. The only issue is all your BIOS settings will be reset and the time and date will be inaccurate. You will also be unable to save BIOS settings.

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

DSL (Digital Subscriber Line) uses POTS (Plain Old Telephone Service) lines to provide high-speed internet access. If the POTS lines are not working, it could cause an internet outage for DSL customers. Fiber and cable internet typically use different types of infrastructure, while satellite internet is not reliant on POTS lines. References: CompTIA A+ Certification Exam: Core 1 - Page 231

If a user is unable to connect a laptop to a projector or videoconferencing system and sees the error message
"No source found," the next step should be to check the display settings on the computer and set them to extend/duplicate. This will ensure that the laptop's display is being output to the external device. References:
CompTIA A+ Certification Exam Guide, pg. 514