<prompt> X-ray features of ASD are all exceptRight atrial enlargementLeft atrial enlargementPulmonary plethoraSmall aortic knockle  <response>: Radiological features of ASD:- Normal size heart or mild cardiomegaly, normal or enlarged pulmonary artery, pulmonary plethora, enlarged right atrium and ventricle, normal size left atrium, small aortic knob. 