This option correctly illustrates the standard procedure for mapping a classification file in Marketing Cloud Intelligence. The source file, Campaign Category Classification, is treated as a separate dimension data stream. Within its mapping, the Campaign ID column (the unique identifier) is correctly mapped to the Campaign Key field in the data model. This establishes the crucial link, or relationship, between the classification file and any other data stream that uses the Campaign Key (like the main Twitter Ads file). This allows the attributes, such as Campaign Category, to enrich the primary performance data.

A. This option also shows a correct mapping for the creative classification file. However, in a single-choice format where multiple options demonstrate the same correct principle, one must be selected.

B. This option also shows a correct mapping for the placement classification file, following the same valid procedure as options A and C.

D. This option is fundamentally incorrect. It attempts to map classification IDs within the main data stream (Twitter Ads). Classification files must be processed in their own data streams to establish a parent-child relationship with the main data.

1. Salesforce Help, Marketing Cloud Intelligence: Map Data. This document outlines the core principles of mapping source data fields to the Marketing Cloud Intelligence data model fields. The correct options (A, B, C) follow this principle by mapping a source ID to a data model Key. The document states, "During the mapping stage, you map the fields from your source file to the relevant Marketing Cloud Intelligence fields." This process is shown correctly in options A, B, and C.

2. Salesforce Help, Marketing Cloud Intelligence: Create a Parent-Child Relationship in a Data Stream. This guide explains how to enrich a data stream (child) with data from another (parent), such as a classification file. It specifies: "To create a parent-child relationship, the parent data stream must contain a key that also exists in the child data stream." Options A, B, and C correctly configure the "parent" (classification) data stream by mapping its identifier to the shared data model key (Campaign Key, Creative Key, etc.), which is the foundational step for this relationship. Option D incorrectly conflates the child and parent mapping steps.