Which process involves arranging items in a systematic order?

The process of arranging items in a systematic order is best defined as sorting. Sorting refers to the methodical organization of items based on a specific criterion, which could include numerical order, size, color, or any other classification that allows for a clear arrangement of items for ease of access and retrieval.

In the context of the options provided, alphabetizing falls under the broader category of sorting and specifically pertains to organizing items based on the order of letters in the alphabet. While it is a systematic order, it does not cover the full scope of sorting as it is a specific criterion.

Cataloging and categorizing involve additional layers of complexity. Cataloging typically refers to creating a comprehensive list or record of items, often including details about those items. Categorizing involves grouping items into defined categories or classes, which may or may not involve a specific order within those categories.

Thus, sorting represents the most encompassing and accurate description of the process involved in organizing items systematically.