The requirement is to group several individual marketing campaigns (TV, radio, print, social) under a single banner ("New Runners") and aggregate their statistics. This is the exact purpose of the Salesforce Campaign Hierarchy feature. This hierarchy is created by populating the standard Parent Campaign field on the child campaign records. By linking the individual campaigns to a parent "New Runners" campaign, Salesforce automatically rolls up key metrics like the number of responses, leads generated, and opportunities created, providing a consolidated view of the entire marketing effort.

A. Junction object: This is used for creating many-to-many relationships and is an unnecessarily complex custom solution for a standard Salesforce feature.

C. Lookup relationship: This is too generic. While the Parent Campaign field is a lookup, this option isn't specific enough to describe the campaign hierarchy feature.

D. Master-detail relationship: This is incorrect as a standard object like Campaign cannot be on the detail side of a master-detail relationship with itself.

1. Salesforce Help, "Set Up a Campaign Hierarchy": "To group campaigns together, create a parent campaign and add other campaigns below it in a hierarchy. The metrics from the child campaigns roll up to the parent, so you can see aggregated results for the entire group."

2. Salesforce Help, "Campaign Hierarchy Fields": This document details the specific fields used for hierarchies, including ParentId (the API name for the Parent Campaign field) and the aggregated fields like HierarchyNumberOfLeads, HierarchyNumberOfContacts, and HierarchyAmountAllOpportunities.

3. Salesforce Help, "View Campaign Hierarchy Statistics": "Campaign hierarchy statistics show aggregated data for a parent campaign and all the campaigns below it in the hierarchy... The Campaign Hierarchy related list on a campaign detail page shows the campaigns that are part of the hierarchy."