This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Congenital Talips Eqino Varvs (C.T.E.V.), Subject name: Orthopaedics
Most common cause of CTEV - 
Select and explain. 
A. Arthrogryposis multiplex congenita, B. Spina bifida, C. Idiopathic, D. Neural tube defect
C: Idiopathic
Answer: C: Idiopathic 
Explanation: Ans. is 'c' i.e., Idiopathic Causes of CTEVo CTEV may be either primary or secondaryPrimary or IdiopathicIt is the most common type of CTEVFoot deformity (CTEV) is the only manifestation, otherwise musculoskeletal system is normal.SecondaryCTEV is a local manifestation of a systemic syndrome.Causes areNeurological disorders & neural tube defects eg myelomeningocele, & spinal dysraphismParalytic disorder (due to muscular imbalance) as polio, spina bifida, myelodysplasia, & Fredreich's ataxiaArthrogryposis multiplexaLarsen syndromeFreeman- sheldon syndromeDiastrophic dwarfismSacral agenesis, tibial deficiency, constriction rings & amniotic bands