Which of the following is not true with respect to deadlock prevention and deadlock avoidance schemes?

• A. In deadlock prevention, the request for resources is always granted if resulting state is safe
• B. In deadlock avoidance, the request for resources is always granted, if the resulting state is safe
• C. Deadlock avoidance requires knowledge of resource requirements a priori
• D. Deadlock prevention is more restrictive than deadlock avoidance