Comprehensive and Detailed Explanation:

The correct answer is D — Contact Builder Attribute Groups.

Contact Builder Attribute Groups allow you to combine multiple Data Extensions (e.g., purchases and loyalty membership) into one relational view.

Then you can easily query and filter based on conditions like "purchase date in last 6 months AND not a loyalty member."

❌Why others are wrong:

A: Behavioral Triggers are related to real-time actions like website behavior, not cross-data queries.

B: Advertising Studio is for paid advertising, not internal audience segmentation.

C: Customer Data Platform (CDP) would be overkill unless NTO had an enterprise-wide CDP already (which isn’t mentioned).

Exact Extract from Salesforce Official Documentation:

Salesforce Help — Contact Builder Attribute Groups Overview:

"Use Attribute Groups to define and model relationships between data extensions and organize contact attributes to create targeted audiences."

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

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