Most common cause of infection caused by intravascular catheter ?

Ans. is 'b' i.e., Coagulase negative staphylococci "Staph. epidermidis is a coagulase negative staphylococcus, which has predilection for growth on implanted foreign bodies such as intravascular catheters, shunts, aificial hea valves and prosthetic appliances, leading to bacteremia".