A company uses B2C Commerce, Marketing Cloud, and Service Cloud and requires that customers create...

Option D is correct because B2C Commerce creates a customer ID when a customer registers an account before making their first purchase, but the primary record should be created through Service Cloud using an external ID field that matches the customer ID from B2C Commerce. This way, Service Cloud can store additional customer information and provide a single source of truth for customer data across multiple Salesforce clouds.

Option A is incorrect because Service Cloud does not create a customer ID when a customer registers an account on B2C Commerce, nor does it create an additional ID to be used as the primary record. Service Cloud uses an external ID field that matches the customer ID from B2C Commerce to create or update customer records.

Option B is incorrect because B2C Commerce does not create an additional ID to be used as the primary record when a customer registers an account. B2C Commerce only creates a customer ID that can be matched with an external ID field in Service Cloud or other Salesforce clouds.

Option C is incorrect because Marketing Cloud does not create a customer ID when a customer registers an account on B2C Commerce, nor does it create a primary ID that should be used by other Salesforce clouds. Marketing Cloud uses subscriber keys that can be mapped to customer IDs from B2C Commerce or other external systems.

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