When Hospitals Began to Be Reimbursed Based on Diagnosis-Related Groups

When hospitals began to be reimbursed based on diagnosis-related groups, the average patient length of stay decreased. Why?

A) Coding became timelier and more accurate.
B) A PPS implies a financial incentive to discharge patients sooner.
C) More patients were admitted with illnesses that did not require long stays.
D) Diagnoses became more accurate and therefore patients could be treated more quickly.