This is a governance decision before it is a configuration click. 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. The proper configuration is C. Use Data Loader to update leads using the CSV file.; D. Select Insert Null Values in Settings. This is the option that best matches the Salesforce responsibility being tested under Data Modeling and Management.
A practical administrator would confirm the object context, the user action, and whether the result must be stored, calculated, displayed, automated, approved, or deployed. Here the selected answer is the one that acts at the correct point in that chain. It keeps the configuration declarative and avoids inventing a process around a problem that Salesforce already has a native feature to solve.
The rejected choices solve different problems. A (Select the correct record type.) is less defensible because it is not the most maintainable declarative control for this design. B (Use Import Wizard to update leads using the CSV file.) should be rejected because Import Wizard is useful for guided imports, but it is limited by object support, volume, and operation type. The configuration remains understandable for future admins because the decision is visible in metadata rather than buried in a workaround.
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