This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pediatric orthopedics, Subject name: Orthopaedics
[{'content': 'The primary defect in CTEV are the following Except \nSelect and explain. \nA. Equinus, B. Adduction, C. Calcaneus, D. Varus', 'role': 'user'}, {'content': 'Answer: C \nExplanation: CTEV deformities:* Equinus deformity occurs primarily at the ankle joint. Other tarsal joints also contribute to it.* Inversion deformity occurs primarily at the subtalar joint. The inveed calcaneum takes the whole foot with it so that the sole faces medially.* Forefoot adduction deformity occurs at the midtarsal joints, mainly at the talonavicular joint.* Forefoot cavus deformity is the result of excessive arching of the foot at the mid-tarsal joints Ref: Maheshwari 6e pg 210.', 'role': 'assistant'}]