Which term describes the arrangement of objects, numbers, or letters in a sequence?

The term that best captures the arrangement of objects, numbers, or letters in a sequence is "order." When we talk about "order," we are referring to the specific sequence or arrangement in which these items are organized, which is an essential concept in areas like mathematics and logic. For example, in mathematics, sorting numbers in ascending or descending order is a common practice; it helps in understanding their relationships.

While "pattern," "selection," and "series" are related concepts, they do not precisely define the aspect of arrangement in a sequence. Patterns refer to a repeated or recurring design, selection indicates a choice from a group, and series typically refers to a sequence of numbers that follow a specific rule but does not inherently emphasize the arrangement aspect. Thus, "order" appropriately describes the focus on how items are sequenced.