Chief Extensor at knee joint is: (A) Biceps femoris, (B) Quadriceps femoris, (C) Semitendinosus, (D) Semimembranosus
Answer is B. Quadriceps femoris is knee Extensor. Hamstrings (Biceps femoris long head, Semitendinosus, Semimembranosus and Adductor magnus) are Knee Flexors.