The uploaded study guide identifies B. Grid as the correct SLDS utility.
The requirement describes a responsive layout in which content must adapt as available screen width changes. Elements may occupy multiple columns on wider screens and then wrap into additional rows when horizontal space becomes constrained.
A Grid system is designed precisely for this type of flexible page structure. It allows designers and developers to organize content into responsive rows and columns rather than relying on fixed positioning.
Option A, Float, can affect how individual elements position themselves relative to surrounding content, but it does not provide the structured, flexible responsive-layout system required by the scenario.
Option C, Alignment, controls positioning or distribution of content but does not itself define the responsive column-and-row layout architecture described.
The underlying UX principle is that responsive design should adapt the interface to varying screen sizes without requiring a completely separate page for each device. A grid gives the layout a systematic structure for resizing, wrapping, and repositioning content while retaining hierarchy.
Therefore, when the design requirement explicitly describes columns that can expand and wrap into new rows, the SLDS Grid utility is the appropriate solution.
Study Guide reference/topics: SLDS Grid, responsive design, flexible layouts, columns and rows, Salesforce Lightning Design System.
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