Answer: Option C. -> The address of a document or “page” on the world wide web

Answer: Option D. -> Digital Subscefer Line (DSL)
DSL is a method of internet access that uses a phone line to transmit data, but offers faster access speeds than traditional dial-up connections. It works by dividing the phone line into separate channels, allowing both voice and data to be transmitted simultaneously. Here are some key points to consider about DSL:

• DSL connections can offer download speeds of up to 100 Mbps, which is much faster than dial-up (which typically tops out at 56 Kbps).
• DSL can be used to deliver internet access over both traditional copper phone lines and newer fiber-optic lines.
• There are different types of DSL connections, including Asymmetric DSL (ADSL) and Symmetric DSL (SDSL). ADSL is more commonly used for residential internet access, as it offers faster download speeds than upload speeds, while SDSL offers equal upload and download speeds and is often used for businesses.
• To use DSL, you need a DSL modem, which connects to your phone line and your computer or router. The modem translates the data sent over the phone line into a format that can be used by your devices.
• DSL is a popular choice for people who live in areas where cable or fiber-optic internet access is not available or is too expensive.

In contrast, here's a brief overview of the other options:

• Cable access: This method of internet access uses the same coaxial cables that are used to deliver cable TV signals. It can offer fast download speeds, but upload speeds may be slower than DSL. Cable internet access is typically more widely available than DSL.
• Satellite access: This method of internet access uses a satellite to transmit data to and from your device. It can be a good option for people who live in rural areas, but it can be more expensive and may not offer the same speeds as DSL or cable.
• Fiber-optic service: This is a newer type of internet access that uses fiber-optic cables to transmit data. It can offer very fast speeds, but it may not be available in all areas and can be expensive.

Answer: Option C. -> Space ( )

Answer: Option B. -> The letters, www.
A URL (Uniform Resource Locator) is a string of characters that provides a way to identify and locate a resource on the Internet. It consists of several components, including a protocol identifier, domain name, and path to the resource. However, not all URLs contain all of these components.
Let's examine each option to determine which must be contained in a URL:
A. A protocol identifier: This is the scheme used to access the resource, such as "http://" or "https://". While most URLs do include a protocol identifier, it is not always necessary. For example, many web browsers will automatically assume "http://" if no protocol is specified.
B. The letters, www.: This is not strictly necessary, but it is commonly used to indicate a website. "www" stands for "World Wide Web" and was originally used to distinguish web pages from other types of content on the Internet. However, many websites now omit "www" from their URLs, so it is not a requirement.
C. The unique registered domain name: This is the main part of the URL and is used to identify the server that hosts the resource. It is essential for locating the resource and is always included in a URL.
D. www. and the unique registered domain name: This option is not necessary since "www" is not a required part of a URL, as discussed above.
E. None of the above: As explained above, option B is correct, so this option is incorrect.
In summary, a URL must contain a protocol identifier (usually) and a unique registered domain name (always), but the letters "www" are not necessary.

Answer: Option B. -> webmail interface

Answer: Option C. -> File server