DreamHouse Realty wants to make sure an Opportunity has a field, Expected_Close_Date c, populated before...

The correct answer is B. Validation Rule.

DreamHouse Realty wants to prevent an Opportunity from entering the Qualified stage unless Expected_Close_Date__c is populated. A validation rule is the correct tool because Salesforce validation rules check whether record data meets specified criteria before the user can save the record.

A validation rule could check:

Stage = Qualified

AND

Expected_Close_Date__c is blank

If both are true, Salesforce blocks the save and displays an error message.

A. Page Layout can make a field visible or required on a layout, but it cannot conditionally require the field only when Stage equals Qualified.

C. Activity History is unrelated.

D. Record Type controls business processes and layouts but does not enforce this condition by itself.

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