What is the main characteristic of the hexadecimal numbering system?

The hexadecimal numbering system is primarily characterized by its use of 16 symbols to represent values. This includes the digits 0 through 9, which represent values zero to nine, and the letters A through F, which represent values ten to fifteen. This combination allows for a more compact representation of binary data, which is crucial in various fields, especially in computing and digital electronics.

In the context of digital systems, hexadecimal is often used because it can represent large binary numbers in a format that is easier for humans to read and understand. For example, one hexadecimal digit corresponds directly to four binary digits (bits), making it simpler to convert between binary and hexadecimal.

The other options do not accurately describe the hexadecimal system. While it does include the digits 0-9, it is not solely composed of them. The attempt to connect hexadecimal with exclusive use for representing binary numbers is misleading; it's a system in its own right, serving as a shorthand for binary rather than being limited to it. Lastly, the statement about operating in Base 8 is incorrect, as hexadecimal actually operates in Base 16. Thus, the defining feature of the hexadecimal system is indeed its inclusion of the letters A-F, making choice B correct.