A.a foramen between the right atrium and the left oneB.……
The fossa ovalis is ().
A.a foramen between the right atrium and the left one
B. existent during the fetus
C.located on the lower part of the right surface of the interatrial septum
D.the thickest part of the wall of the heart
E.a remnant of the fetal heart between the atrium and ventricle