Single-mode fiber (as well as multi-mode fiber) transmits data using beams of light, allowing for high-speed data transfer over flexible fiber-optic cables.
From CompTIA A+ 220-1101 Official Study Guide, Objective 2.1 - Networking media:
"Fiber optic cables transmit data using light. Single-mode fiber is used for long-distance, high-speed communication." Verified Source:
CompTIA A+ Core 1 (220-1101) Official Study Guide, Chapter 2: Networking Media CompTIA Exam Objectives 220-1101, Domain 2.1

If a desktopfails to power on entirely, the most probable cause is afaulty Power Supply Unit (PSU). If there are no lights, fans, or POST beeps, the PSU may have failed, cutting off all power to the motherboard and components.
Option B (GPU):Could prevent video output, but the system would still power on and beep.
Option C (RAM):Missing or faulty RAM would cause POST errors but not prevent startup entirely.
Option D (CPU):A bad CPU may cause POST failure, but the system would usually at least power on.
CompTIA A+ Core 1 Exam Objective Reference:
Objective 3.5: Given a scenario, troubleshoot problems related to motherboards, RAM, CPU, and power.

If two devices have thesame static IP address, anIP conflictoccurs. This results in both devices being intermittently disconnected or unable to communicate on the network. It's a common mistake when copying configurations manually.
Option B:DNS conflicts wouldn't cause total disconnection and wouldn't occur just from copying IP settings.
Option C:A cable issue would only affect one workstation.
Option D:Switchport security issues wouldn't affect both machines simultaneously unless port security was configured very specifically.
CompTIA A+ Core 1 Exam Objective Reference:
Objective 2.6: Given a scenario, configure and troubleshoot network connectivity.

CompTIA A+ identifies satellite internet as the connection type most susceptible to weather-related interference, particularly rain, snow, and heavy cloud cover. This phenomenon is known as rain fade. Satellite connections rely on high-frequency microwave signals transmitted between a dish antenna at the customer site and an orbiting satellite. Moisture in the atmosphere absorbs and scatters these signals, causing latency spikes, reduced bandwidth, or complete signal loss during storms.
Fiber (A) uses light signals through glass fiber and is immune to electromagnetic and weather interference. Cable internet (B) uses shielded coaxial lines buried or run overhead, but rain does not affect signal quality in normal conditions. DSL (D) uses telephone lines, which may degrade with physical line issues, but not directly due to rain in the same way satellite is affected.
Thus, satellite internet is most likely to experience signal degradation during rain conditions.

The first security step after deploying a new router is to change the default administrative password. Default credentials are well known and pose a security risk if left unchanged.
From CompTIA A+ 220-1101 Official Study Guide, Objective 2.3 - Secure a wireless network:
"Always change default administrative credentials before further configuration to prevent unauthorized access." Verified Source:
CompTIA A+ Core 1 (220-1101) Official Study Guide, Chapter 2: Wireless Security CompTIA Exam Objectives 220-1101, Domain 2.3