What option would you use to customize the horizontal or vertical axis styling?

The option to customize the horizontal or vertical axis styling is found in the "Expand Axis Section." This section allows users to modify various aspects of the axes on charts or graphs within Smartsheet, including the font type, size, color, and other stylistic elements. Such customization is crucial for enhancing the readability of the chart and ensuring that it effectively communicates the desired information to stakeholders.

Being able to adjust the axis styling not only improves the visual appeal but it also aids in highlighting important data trends or comparisons, making it easier for viewers to understand the chart's message at a glance.

The other options, while useful in different contexts, do not pertain to axis styling. Creating a group is typically used for organizing tasks or resources rather than for visual customization on charts. Adding gridlines helps in improving the clarity of the data presentation, but it does not change the styling of the axes themselves. Sending an update request relates to project communication and task management rather than graphic representation, making it irrelevant for axis customization.