Which two approaches should the Architect take?

DreamHouse Realty has an integration that creates records in a Salesforce Custom Object. The Custom Object has a field marked as required on the page layout.

DreamHouse Realty has noticed that many of the records coming from the external system are missing data in this field.

The Architect needs to ensure this field always contains data coming from the source system.

Which two approaches should the Architect take? (Choose two.)
A . Set up a Validation Rule to prevent blank values.
B . Create a Workflow to default a value into this field.
C . Make the field required at the object level.
D . Communicate that DreamHouse Realty’s external system has bad data.

Answer: AC