<prompt> All of the following are true about coronary aery, EXCEPT?Right coronary aery lies in right anterior coronary sulcusLeft anterior descending aery is a branch of left coronary aeryUsually 3 obtuse marginal aeries arise from left coronary aeryIn 85 cases posterior descending interventricular aery arises from right coronary aery  <response>: Only one obtuse marginal aeryOM1 arise from circumflex branch of left coronary aery. This obtuse marginal branch serve as a boundary between the proximal and distal poion of left circumflex aeryLCx. Poion of left circumflex aery proximal to obtuse marginal aery is called proximal LCx, whereas the segment below OM1 is the distal LCx. 