This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
Hand to knee gait in polio is due to involvement of which muscle? 
Select and explain. 
A. Gastrocnemius, B. Gluteus medius, C. Quadriceps, D. Hamstring
C: Quadriceps
Answer: C: Quadriceps 
Explanation: Answer-C. QuadricepsDeformity at hip: Flexion, abduction & external rotationDeformity at knee: Triple deformity of flexion' posterior subluxation & external rotationFoot: Equinovarus is most deformity followed by equinovalgus, Calcaneovalgus, calcaneovarusUpper limb: Shoulder and elbow muscles