Which of the Following Is True About Total Knee Arthroplasty

Which of the following is true about total knee arthroplasty (TKA) ?

A) When a cruciate-retaining prosthesis/procedure is used for a TKA,the anterior cruciate ligament (ACL) is not excised,thus providing greater anterior-posterior stability to the knee.
B) A tricompartmental TKA involves replacing not only the articulating surfaces of the proximal tibia and distal femur,but also the tibiofibular articulation.
C) If a semiconstrained or unconstrained prosthetic implant is used,the medial and lateral collateral ligaments (MCL and LCL) must be intact or repairable for adequate postoperative medial-lateral stability of the replaced joint.
D) A mobile-bearing prosthesis typically is selected for the elderly,relatively sedentary patient because this design permits earlier weight bearing than a fixed-bearing design.