If nothing was unclear or difficult, say so. Skip questions about steps you did not experience; use not applicable where appropriate.

What question were you trying to answer?
Which chart was difficult to interpret?
What example would help you choose?

Author notes / illustrative keys where applicable:
1. The question users wanted to answer identifies the comparison task before a chart is chosen. Separate that need from preferences for a particular visual style.
2. A difficult chart identifies the representation or label that obscures the intended comparison. Clarify measured variables and consider a suitable alternative, without assuming a chart preference demonstrates statistical understanding or analytical validity.
3. A useful selection example identifies the guidance needed to connect chart structure with the comparison task. Use labelled synthetic data without implying statistical validity from chart preference.