Answer:
Option). B the ductus venosus; D the ductus arteriosus
Explanation:
In fetal circulation, the structure that connects the umbilical vein with the vena cava is known as ductus venosus. It allows transfer of oxygenated blood to bypass the fetal liver from the placenta. In given diagram, it is represented by letter B.
The structure that connects the pulmonary artery with aorta is known as ductus arteriosus. It allows flow of blood to the aorta from pulmonary artery, which is then transported to placenta for oxygenation. In given diagram, it is represented by letter D.
