A customer wants to integrate a new dataset with pre-existing contacts.

Comprehensive and Detailed Explanation:

The correct answer is B — Create a new data extension and link it to the other data extension.

Best practice is to separate different data streams into different Data Extensions and use relationships (via Contact Builder Attribute Groups) to link them logically.

This allows independent updates from different sources without risking overwriting primary contact data.

❌ Why others are wrong:

A: Adding more fields to the main DE would make the model heavy and harder to manage, especially with separate feeds.

C: Salesforce Data Extensions are specific to CRM integration and not mentioned here.

D: New populations are used when contacts are fully separate audiences, which is not the case here (it's the same contact base).

Exact Extract from Salesforce Official Documentation:

Salesforce Help — Contact Builder Data Relationships:

"Use separate data extensions for distinct types of information and create relationships between them to build a scalable contact data model."

(Source: https://help.salesforce.com/s/articleView?id=sf.mc_cb_data_model.htm )

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