How do variables in DAX primarily improve formula readability?

Variables in DAX enhance formula readability primarily by breaking down lengthy and complex formulas into smaller, more manageable parts. When a formula is composed of multiple components or calculations, using variables allows you to assign meaningful names to these intermediate results. This approach not only clarifies the logic behind each calculation but also improves the flow of the formula, making it easier for someone else (or even the original author later) to follow the thought process.

By segmenting complex calculations into distinct variables, each step can be evaluated independently. This modular approach helps to reduce confusion and allows readers to understand the sequential logic behind the calculations. Furthermore, straightforward variable names can serve as documentation within the formula itself, enhancing overall comprehension without the need for excessive comments.

The other choices, while they touch on important aspects of working with DAX formulas, do not specifically highlight the primary benefit of improving readability through the use of variables. While debugging and visual representation are important functions in DAX, the core advantage concerning readability arises from the structured breakdown that variables provide.