The valves in the heart open and close to move blood in between heart chambers. O a) three directions O b) two directions O c) four directions d) one direction

Hi,

The valves in the heart open and close to move blood in between heart chambers.

d) one direction

answer; /// i believe that the correct answer is (50%);

the answer is: reproductively

i think i spelled it wrong lol

anyways hope i

-lavira: )