The correct answer is A. Design tokens prefixed with "brand", exactly as identified in the uploaded UX Designer study guide.

The question is testing how a design system propagates theme-level design decisions across multiple components. Rather than hard-coding individual color values into every button, icon, or component, SLDS uses named design values represented through design tokens.

The guide specifically identifies tokens prefixed with “brand” as the mechanism used to align components with a custom theme.

This approach improves both consistency and maintainability. If a theme changes, components referencing the appropriate brand token can inherit the updated design value instead of requiring developers to locate and replace numerous hard-coded values.

Option B, JavaScript libraries loaded from a static resource, is not the design-value mechanism described in the question.

Option C, CSS hexadecimal values, represents the opposite of a scalable design-system approach. Hard-coded values make global design changes harder and can cause components to become visually inconsistent over time.

The study-guide principle is that theme-driven interfaces should rely on reusable named design entities rather than duplicated literal values.

Study Guide reference/topics: Design Tokens, brand tokens, themes, component consistency, Salesforce Lightning Design System.

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