Largest heart is found in

All vertebrates possess a ...$A$.... Fishes have a ...$B$... chambered heart with atrium and ventricles. Amphibians and reptiles have a ...$C$... chambered heart. Birds and mammals have ...$D$... chambered heart.
Choose the correct option.

The heart of an elephant is

Where does the bundle of His originate?

The blood pumped by the $A$ ventricle enters the $B$ artery,whereas the $C$ ventricle pumps blood into the $D$. Choose the correct option for $A, B, C$ and $D$.

Select the incorrect statement regarding the heart.