This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thorax, Subject name: Anatomy
If circumflex aery gives the posterior interventricular branch, this circulation is described as 
Select and explain. 
A. Right dominance, B. Left dominance, C. Codominance, D. Undetermined
B: Left dominance
Answer: B: Left dominance 
Explanation: In about 10% of heas,the right coronary is rather small and is not able to give the posterior interventricular branch. In these cases the circumflex aery,the continuation of left provides the posterior interventricular branch and called left dominant. <img src=" /> B D CHAURASIA'S HUMAN ANATOMY UPPER LIMB THORAX-VOLUME1 SIXTH EDITION Page no:265