MCQ pediatric

[A baby girl is considered normal at birth but on the second day of age cyanosis is noted. No murmur is heard and there is no respiratory distress. On the third day, cyanosis is more obvious and the respiratory rate is increased. Which of the following is correct concerning this patient?

A.Cyanosis is most likely due to congenital heart defect.
B.The baby’s colour should improve rapidly after giving 100% 02.

C.Echocardiography can often tell the anatomic state of the newborn’s circulation.

D.The baby’s chest x-ray shows a small heart. This is against the diagnosis of congenital heart disease.

E.The lack of murmur is against the diagnosis of CHt