WPA2 (WiFi Protected Access II) is a WiFi security option that uses encryption and authentication to protect the wireless network from unauthorized access or eavesdropping. WPA2 is the most secure and recommended WiFi security option among the options given. If some light switches are no longer communicating after replacing the wireless router with a new device that uses WPA2, the most likely cause is that the light switches do not support WPA2. The light switches may need to be updated or replaced to be compatible with WPA2. The router operating on a different channel, the key not meeting password complexity requirements, and the SSID not being broadcast are not likely causes of the light switches not communicating after replacing the wireless router with a new device that uses WPA2. Reference: CompTIA IT Fundamentals+ Study Guide: Exam FC0-U61, Second Edition, Chapter 8: Security Concepts, page 311.

A NoSQL database is a type of database that does not use tables, rows, and columns to organize data. Instead, it uses keys and values to store data in a flexible and scalable way. A key is a unique identifier for a piece of data, and a value is the data itself.
For example: { "name": "Alice", "age": 25, "city": "New York" }
In this example, name, age, and city are keys, and Alice, 25, and New York are values.
References: CompTIA IT Fundamentals+ Study Guide: Exam FC0-U61, Second Edition, Chapter 5: Database Fundamentals, page 196.

Explanation
A string is the data type that a developer should use when creating a variable to hold a postal code. A string is a sequence of characters that can represent text, symbols, or numbers. A string can store any value that can be typed on a keyboard, such as "Hello", "123", or "90210". A string is enclosed by quotation marks to distinguish it from other types of data. A postal code is an example of a value that can be stored as a string. References : The Official CompTIA IT Fundamentals (ITF+) Study Guide (FC0-U61), page 139.

Satellite would be the best choice for Internet service for a home in a remote location that has no connectivity to existing infrastructure. Satellite Internet service uses satellites in orbit to provide wireless Internet access to users who have a satellite dish installed at their location. Satellite Internet service can cover areas where other types of Internet service are not available or reliable, such as rural or remote locations. Satellite Internet service can offer high-speed broadband connections, but it may also have drawbacks such as high latency, weather interference, and data caps. Reference : The Official CompTIA IT Fundamentals (ITF+) Study Guide (FC0-U61), page 168.

The operating system is the software solution that ensures that programs running simultaneously on a workstation do not utilize the same physical memory. The operating system is the software that manages the hardware and software resources of a computer, such as the CPU, memory, disk, network, and applications. The operating system uses memory management techniques, such as virtual memory, paging, and segmentation, to allocate and deallocate physical memory to programs as needed, and to prevent memory conflicts or errors. A disk optimizer is a software solution that improves the performance of a disk drive by rearranging the files and free space on the disk to reduce fragmentation and increase access speed. A disk optimizer does not affect the physical memory usage of programs. A type 1 hypervisor is a software solution that creates and runs multiple virtual machines on a single physical machine by directly controlling the hardware resources. A type 1 hypervisor does not ensure that programs running simultaneously on a workstation do not utilize the same physical memory, but rather that virtual machines running simultaneously on a physical machine do not utilize the same hardware resources. An anti-malware is a software solution that protects a computer from malicious software, such as viruses, worms, trojans, spyware, or ransomware. An anti-malware does not ensure that programs running simultaneously on a workstation do not utilize the same physical memory, but rather that programs running on a workstation do not contain malicious code or behavior. References: The Official CompTIA IT Fundamentals (ITF+) Student Guide (Exam FC0-U61), Chapter 4: Operating System Fundamentals