The following figure shows the human heart. LA = left auricle; LV = left ventricle; RA = right auricle; RV = right ventricle. Where are the valves located?
1
At all positions: 1, 2, 3, 4, 5 and 6
2
At positions 1, 2, 4 and 6
3
At positions 2, 3, 4 and 5
4
At positions 4, 5 and 6