Northern Trail Outfitters wants to change a master-detail Relationship on Account to a lookup relationship...

The correct answer is D.

Salesforce allows converting a master-detail relationship to a lookup relationship only when there are no roll-up summary fields on the master object that summarize the detail records. Salesforce documentation states that after a roll-up summary field exists on an object, the object’s master-detail relationship can’t be converted into a lookup relationship.

In this case, if Account has roll-up summary fields based on related Park records, Salesforce blocks the conversion.

A is incorrect because a flow using Account does not normally prevent converting the relationship. B is incorrect because formulas on Park referencing Account are not the primary restriction. C is incorrect because custom objects do not need at least one master-detail relationship for reporting.

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