The diagram shows the major chambers and blood vessels of the human heart.
Blood returns from the body back to the heart and is then pumped to the lungs.
Which order of structures does this blood go through?
Q→R→PQ \rightarrow R \rightarrow PQ→R→P
T→S→PT \rightarrow S \rightarrow PT→S→P
Q→R→UQ \rightarrow R \rightarrow UQ→R→U
T→S→UT \rightarrow S \rightarrow UT→S→U