Regarding the movements at the knee joint:

• A. popliteus unlocks the extended knee by producing medial rotation of the femur
• B. there is no active rotation of the extended knee
• C. passive extension of the knee does not result in locking of the joint
• D. the posterior cruciate ligament prevents backward displacement of the femur on the tibial plateau
• E. the major role of the menisci is in flexion/extension of the knee