The correct answer is C. Numerical classification.
Alphabetical classification is based on the order of letters in the alphabet. Alphanumeric classification is based on the order of letters and numbers. Geographical classification is based on the location of objects on Earth. Numerical classification is based on the order of numbers.
For example, in a library, books are often classified by their Dewey Decimal Classification number, which is a numerical system that assigns a unique number to each book based on its subject matter. This system allows librarians to easily find books on a particular topic.
Another example of numerical classification is the ISBN (International Standard Book Number), which is a unique 13-digit number assigned to each book. The ISBN is used to identify books and to track their sales and distribution.
Numerical classification is a useful tool for organizing information and for finding information quickly and easily.