An 8 year old boy presented with fever and cough. Chest x ray was done with the following finding- Which of the following is the abnormality leading to above chest x ray finding?

Chest x ray reveals DEXTROCARDIA. Abnormalities of Cardiac Looping Dextrocardia : hea lies on the right side of the thorax instead of the left and it occurs when the hea loops to the left instead of the right. The defect may be induced- during gastrulation, when laterality is established, or Slightly later when cardiac looping occurs.