The important question is which feature owns the result. The proper configuration is A. Import Wizard. The requirement in the stem is: Cloud Kicks asked the app builder to insert a list of 25,000 records using Deduplication for the Delivery custom object. Which tool should be used? The selected option addresses that requirement at the point where Salesforce actually evaluates the behavior.
The underlying concept is data import and matching. Salesforce import tools differ by data volume, matching logic, and operation. Data Import Wizard is guided and duplicate-aware for supported objects; Data Loader is stronger for larger updates, upserts, and clearing values. That is why this answer is more defensible than a workaround. It can be reviewed in Setup, included in the correct deployment path, and tested by impersonating or logging in as a representative user where appropriate.
The rejected choices solve different problems. B (Data Loader) should be rejected because Data Loader is an administrative data tool; it does not replace metadata configuration or user-interface design. C (Lightning Object Creator) would be fragile here because A Lightning component changes the interface; it does not automatically solve security, relationship, or data-quality requirements. D (Schema Builder) does not fit cleanly; it solves a symptom of the problem rather than the Salesforce mechanism that owns the result. The configuration remains understandable for future admins because the decision is visible in metadata rather than buried in a workaround.
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