Not a component of tetralogy of fallot -

Ans. is 'd' i.e., Patent ductus arteriosus Tetralogy of falloto TOF is the commonest cyanotic congenital heart disease.o It has four componentsi) VSDii) Pulmonic stenosisiii) Overriding or dextroposed aortaiv) Right ventricular hypertrophyo Pulmonic stenosis (right ventricular outflow obstruction) is mainly due to infundibular stenosis. Obstruction at pulmonary valve level (valvular stenosis) is very uncommon (only 10%)."Pentology of fallot consists of components of TOF plus atrial septal defect"