<prompt> Which of the following is false regarding coronary circulation ?Anterior 23 of septum is supplied by LCAPosterior 13 of septum is supplied by RCARight bundle branch is supplied by RCALeft bundle branch is supplied by LCA  <response>: Right coronary aery supplies i SA node in 65, ii whole conducting system AV bundle, bundle of his, pa of left bundle branch except RBB and pa of left branch of AV bundle, iii posterior pa of ventricular septum, iv most of right ventricle except small pa adjoining anterior interventricular groove and small pa of left ventricle adjoining posterior interventricular groove.Left coronary aery supplies i most of the left atrium, ii most of the left ventricle including apex, iii small pa of right ventricle odjoining anterior interventricular septum, iv anterior 23 of ventricular septum, v RBB, LBB and vi SA node in 35 of cases. 