Cloud Kicks has been tracking how many participants wear the company's shoes in each marathon. The administrator creates two custom objects: Races…

A master-detail relationship cannot be deleted if it is referenced by other components in Salesforce. A roll-up summary field on the master object (Races) is directly dependent on the master-detail relationship with the child object (Runners) to perform its calculation. To remove the master-detail relationship field, this dependency must be removed first. Therefore, the administrator must delete the roll-up summary field from the Races object before the system will allow the master-detail relationship field to be deleted.

A. Changing the field type to a Lookup is an alternative to deletion, not a prerequisite for it. This action also requires removing roll-up summary fields first.
B. 'Allow Reparenting' is a feature of the master-detail relationship that allows child records to be moved to a new parent; it does not remove dependencies.
C. Cascade deletion is an inherent property of a master-detail relationship. There is no standard setting to simply "uncheck" this behavior to enable field deletion.

1. Salesforce Help, Considerations for Relationships, Section: "Master-Detail Relationship Field". "You can’t delete a custom object or field if it’s referenced in a roll-up summary field."

2. Salesforce Object Reference Guide, Custom Field Attributes. This guide details the dependencies of field types, implicitly noting that components like roll-up summaries must be removed before the fields they reference can be deleted. (This concept is foundational and covered in object relationship documentation).