The study guide explicitly identifies C. Become familiar with the Salesforce Lightning Design System (SLDS) component blueprints as the correct first step.
Before designing a new Lightning component, the UX Designer should understand the established Salesforce patterns applicable to that type of interface. SLDS Component Blueprints provide the structural and visual reference for Salesforce-style components and therefore give the designer a foundation before introducing custom decisions.
Option A begins with design tokens. Tokens are useful for consistent values such as spacing, sizing, or visual attributes, but importing them before understanding the component pattern would start at too low a level. The designer first needs to understand the component architecture and behavior.
Option B focuses on AppExchange packages. AppExchange can provide complete applications and extensions, but reviewing packages is not the first design step identified in this scenario.
The underlying principle is design-system-first thinking. Before creating a new component, designers should understand how Salesforce already represents similar controls and interactions. This reduces inconsistency and makes it easier for developers and users to recognize established Lightning patterns.
Study Guide reference/topics: SLDS Component Blueprints, component design, Lightning, design-system consistency, Salesforce Lightning Design System.
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