Which Are Functions Performed by the Fibrous Skeleton of the Heart

Which are functions performed by the fibrous skeleton of the heart?
A: Separates the atria and ventricles
B: Anchors the heart valves
C: Provides electrical insulation between the atria and ventricles
D: Provides the framework for the attachment of the myocardium
E: None of these are true functions of the fibrous skeleton of the heart.

A) a,d
B) b,d
C) a,c,d
D) a,b,c,d
E) e