Which Statements Are Examples of Hypotheses

Which statements are examples of hypotheses?

A) Hospitals staffed with primarily bachelor-prepared nurses will have lower mortality rates than hospitals staffed with primarily associates-prepared nurses.
B) More than 80% of the patients with catheter-associated urinary tract infections did not have any signs or symptoms of infection.
C) Patients who receive ondansetron preoperatively will experience lower rates of nausea and vomiting than patients who do are not premedicated.
D) The greatest risk factor for developing ventilator-associated pneumonia was the length of time that the patient was intubated.
E) Ultraviolet light disinfection of equipment is a nontoxic,effective method for prevention of Clostridium difficile infection.