Question

which structure is highlighted and indicated by the leader line?
multiple choice
fossa ovalis
trabeculae carneae
pectinate muscles
interatrial septum
papillary muscles

Explanation:

The question is about identifying a heart structure. The fossa ovalis is a depression in the interatrial septum, and from the diagram (showing a heart model and specimen), the highlighted structure matches the fossa ovalis. Other options: trabeculae carneae are in ventricles, pectinate muscles are in atrial walls (but the location here fits fossa ovalis), interatrial septum is the wall, papillary muscles are in ventricles. So the correct structure is fossa ovalis.

Answer:

A. Fossa ovalis