In the following diagram which of the following isare true I

In the following diagram, which of the following is/are true? In the relationship between Physician and PatientVisit, the Physician is optional. In the relationship between Patient and PatientHistory, the Patient is optional. In the relationship between the PatientHistory and Patient, the Patient is required. In the relationship between Physician and PatientVisit, the PatientVisit is required.

Solution

C,D are true.

Patient is the required entity in the relationship between PatientHistory and Patient because without Patient there will be no history.

PatientVisit is a required entity in the relationship between Physician and PatientVisit because without PatientVisit a physician cannot attend.