Explanation: In the SaaS (Software as a Service) model, the service provider manages the infrastructure, platforms, and software applications, including maintenance tasks such as application patching. Users access the applications over the internet, and the provider is responsible for ensuring the software is up to date, secure, and performing optimally. This model contrasts with IaaS (Infrastructure as a Service) and PaaS (Platform as a Service), where the customer has more control and responsibility over the environment and may need to manage patching for applications they develop or install.
References: SaaS is designed to relieve users from the complexity of software maintenance, including patch management, as highlighted in cloud computing service model descriptions.

Explanation: If a laptop has been returned for a screen repair and the owner insists the screen is broken, but occasionally a faded image is able to be seen in very bright settings on the desktop, the first step the repair technician should take is to ensure the backlight is functioning as expected. If the backlight is faulty, the screen may appear to be broken, but it may only be dim or too dark to be visible.

Explanation: RAID 10 array is often used for server virtualization as it provides both redundancy and performance benefits. It uses a combination of mirroring and striping to provide both fault tolerance and improved I/O performance. An optical disk drive or eMMC storage device would not provide enough storage or performance for a VM host server, while a 15,000rpm drive may provide good performance but would not provide redundancy for fault tolerance. Therefore, a RAID 10 array is the best option for cost-effective storage that will be used for all VMs that run from the server.

Explanation: The first step in troubleshooting is to reproduce the issue. This ensures that the problem exists as reported, and the technician can observe it directly. In this case:
✑ Testing the wireless speed on the user's laptop while connected to the new router allows the technician to verify the problem and gather evidence for further troubleshooting.
✑ Reproducing the issue helps confirm whether the problem is with the laptop, the router configuration, or other network factors.
Key Concepts:
✑ CompTIA Troubleshooting Steps:
CompTIA A+ Exam Objectives References:
✑ 220-1101, Section 5.1: Details the best practices for troubleshooting, including starting with verifying the problem exists as reported.

Explanation: Fiber-optic connections offer the highest speeds and bandwidth, making it the best choice for fast data transmission between nearby locations.

Explanation: If users are only able to save a small number of pictures on the microSD cards before running out of space, it suggests a formatting issue. Improper or incomplete formatting can lead to the card not utilizing its full storage capacity, resulting in significantly less available space for storing pictures. Formatting the microSD cards correctly would ensure the file system on the cards is set up properly, allowing the devices to use the full capacity of the cards for storage. Compatibility, UHD storage capability, and camera storage settings are less likely to be the issue in this scenario.
References: The necessity of proper formatting for storage devices is a fundamental aspect of managing digital storage, as outlined in the basic principles of digital storage and file systems.

Explanation: The technician has identified the symptoms (slow performance and random pop-ups) and must now establish a theory of probable cause, such as malware or spyware infection. This step aligns with the CompTIA troubleshooting methodology.
✑ Why Not A (Establish a knowledge base): This is irrelevant at this stage;
knowledge bases are used for reference and documentation.
✑ Why Not C (Establish a new theory and consider escalating): The technician has not yet created or tested a theory, making escalation premature.
✑ Why Not D (Establish a plan of action): Planning an action occurs after determining the cause of the problem.
CompTIA A+ Exam Reference: Core 2 (220-1102), Section 3.1, troubleshooting methodology.

Explanation: Dot Matrix printers do not use heat, they use a pin striking an inked ribbon (for the first copy, the subsequent copies are handled by the carbon paper) The ribbon is low on ink or missing and must be replaced to get proper output in a dot matrix printer that uses carbon paper.

References: CompTIA A+ Certification Exam Guide, Exam 220-1001, Page 361

Explanation: DKIM (DomainKeys Identified Mail) is an email authentication method that attaches a digital signature to outgoing emails to verify the email’s authenticity and detect email spoofing.
✑ SPF (Sender Policy Framework): Specifies which mail servers are authorized to send emails for a domain but does not involve digital signatures.
✑ DNS Pointer (PTR): Used for reverse DNS lookups, not email authentication.
✑ MX Records: Specify mail servers for email delivery but do not authenticate emails.
CompTIA A+ Exam Reference: Core 2 (220-1102), Section 2.4, email security and authentication.

Explanation: Client-side virtualization guest machines require isolation from other guest machines to maintain their security. Isolation ensures that each virtual machine is separated from others and runs its own operating system and applications, making it less vulnerable to attacks from other guest machines.
References: CompTIA A+ Certification Exam Objectives 220-1002 - Virtualization and cloud computing - 4.1