A 46-year-old male , an IV drug abuser presents to OPD with complaints of fatigue, malaise and rigors. His temperature was 38.5degC, pulse -84/min, BP- 130/80 mm Hg .On cardiovascular examination , pan-systolic murmur was heard , loudest at the left sternal border. 3 sets of blood cultures were taken consecutively . Transthoracic echocardiography (TTE) was done , which revealed vegetation on the tricuspid valve with TR.From the given history , which organism is most likely to be positive in blood cultures?