Final answer:
The incorrect statement about obstetric emergencies is that pulmonary embolus is described as sudden cardiovascular collapse, cyanosis, mental status changes, or massive hemorrhage.
Step-by-step explanation:
The incorrect statement about obstetric emergencies is C) Pulmonary embolus is described as sudden cardiovascular collapse, cyanosis, mental status changes, or massive hemorrhage. Pulmonary embolus is actually described as sudden-onset shortness of breath, chest pain worsened by deep breathing or coughing, rapid breathing, rapid heartbeat, and lightheadedness. It is caused by a blockage in the blood vessels in the lungs. Therefore, option C is incorrect.