Choose the Correct Order of the Chambers Through Which Oxygen-Poor $\rightarrow$

Choose the correct order of the chambers through which oxygen-poor blood flows in an amphibian heart.

A) atrium $\rightarrow$ ventricle $\rightarrow$ sinus venosus $\rightarrow$ conus arteriosus
B) atrium $\rightarrow$ conus arteriosus $\rightarrow$ ventricle $\rightarrow$ sinus venosus
C) sinus venosus $\rightarrow$ atrium $\rightarrow$ ventricle $\rightarrow$ conus arteriosus
D) conus arteriosus $\rightarrow$ atrium $\rightarrow$ sinus venosus $\rightarrow$ ventricle
E) ventricle $\rightarrow$ atrium $\rightarrow$ conus arteriosus $\rightarrow$ sinus venosus