The goal is to extract a specific substring ("Delux") from a campaign name ("Ad15X2w&Deluxwal90") that contains multiple, inconsistent delimiters.

1. Calculated Dimensions: This method allows for the creation of a new dimension using formulas to manipulate existing data. A formula using functions like SPLIT() or a combination of SUBSTRING() and FIND() can parse the original string and isolate the desired second position value.

2. Patterns: This feature is designed specifically for extracting values from a dimension using regular expressions (regex). A regex pattern can be defined to capture the text between the first delimiter (&) and the second delimiter (), achieving the desired outcome efficiently.

3. Mapping formula: During data ingestion, formulas can be applied directly in the mapping stage to transform source data. This is functionally identical to a calculated dimension but cleanses the data before it enters the data model.

C. Vlookup: This function is used for data enrichment by looking up a key in a separate table and returning a corresponding value, not for parsing strings within a field.

D. Data Fusion: This feature merges entire data streams based on a shared key (like Date) to create a unified dataset. It does not perform string manipulation on individual dimension values.

1. Salesforce Help, Marketing Cloud Intelligence, Create a Calculated Dimension: "You can create calculated dimensions and measurements to enhance and enrich your data... For example, you can extract the campaign name from a string..." This supports the use of formulas in Calculated Dimensions (A).

2. Salesforce Help, Marketing Cloud Intelligence, Marketing Cloud Intelligence Functions: This document lists string manipulation functions like SPLIT(text, delimiter, index) which can be used in both Calculated Dimensions (A) and Mapping formulas (E). For this specific case, a nested formula like SPLIT(SPLIT([Campaign Name],'&',2),'',1) would work.

3. Salesforce Help, Marketing Cloud Intelligence, Apply a Pattern to a Dimension: "Use patterns to extract a value from a dimension based on a regular expression... For example, you have a campaign name that includes the country, and you want to extract only the country." This directly supports the use of Patterns (B) for this scenario.

4. Salesforce Help, Marketing Cloud Intelligence, Formulas for Data Mapping: "You can use formulas in the mapping stage to manipulate your data as it’s processed into Intelligence." This confirms that the same powerful formula engine is available during mapping, supporting Mapping formula (E).