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 the circumflex aery gives off the posterior interventricular aery, then the aerial supply is called 
Select and explain. 
A. Right dominance, B. Left dominance, C. Balanced dominance, D. Codominance
B: Left dominance
Answer: B: Left dominance 
Explanation: If the circumflex aery gives off the posterior interventricular aery, then the aerial supply is called left dominance. In 65% of the population, the posterior interventricular aery (PIVA) is a branch of right coronary aery and this is called the right dominance. In 10% of the population, PIVA is given by the circumflex aery (a branch of the left coronary aery) and this is called the left dominance. Ref: Gray&;s Anatomy 41st edition Pgno: 1019