Alphanumeric characters can include which of the following?

The correct answer indicates that alphanumeric characters encompass a combination of letters and numbers, which also includes special symbols. The term "alphanumeric" itself is derived from "alphabet" and "numeric," meaning it inherently includes both the alphabetic characters (A-Z, a-z) and numeric digits (0-9).

While some interpretations may consider an extended set that includes special symbols as part of broader computational character sets (such as ASCII or Unicode), the foundational definition of alphanumeric specifically refers to the inclusion of both letters and numbers. Hence, the correct answer expands on this definition by acknowledging how, in various contexts, special symbols can also be involved.

This broader interpretation is why the answer correctly asserts that alphanumeric characters can comprise letters, numbers, and special symbols.