<prompt> Base of the heart is maximally formed by -Left VentricleRight VentricleRight AtriumLeft Atrium  <response>: Ans. is d i.e., Left Atrium The heart has following borders and surfacesA Bordersi Right border:- Formed by right atrium.ii Left border obtuse margin:- Formed mainly by left ventricle and partly by left auricle in its upper most part.iii Inferior border acute margin:- Formed mainly by right ventricle and partly by left ventricle near apex.iv Upper borderMainly by left atrium and partly by right atrium where SVC enters.v Apex:- Formed by left ventricle.B Surfacesi Anterior sternocostal surface :- Formed mostly by right ventricle major and right auricle and partly by left ventricle and left auricle.ii Inferior diaphragmatic surface:- It is formed by left ventricle left 23 and right ventricleright 13. It is traversed by posterior interventricular groove PIV containing PIV branch of RCA.iii Base posterior surface:- Formed mainly by left atrium and partly by right atrium. It is separated from T5 to T8 vertebrae by pericardium, oblique pericardial sinus, esophagus and descending thoracic aorta.iv Right surface:- Mainly by right atriumv Left surface:- Mainly by left ventricle and partly by left auricle. 