This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Lab Investigations, Subject name: Microbiology
All of the following are true about Methicillin resistance in MRSA, except- 
Select and explain. 
A. Resistance is produced as a result of altered PBP's, B. Resistance may be produced by hyperproduction of beta lactamase, C. Resistance is primarily mediated/transmitted plasmids, D. Resistance may be missed at incubation temperature of 370C during susceptibility testing
C: Resistance is primarily mediated/transmitted plasmids
Answer: C: Resistance is primarily mediated/transmitted plasmids 
Explanation: Resistance in MRSA is chromosomally mediated (not plasmid mediated). Resistance is produced as a result of altered PBP's- mediated chromosomal mec A gene which codes for altered PBP- 2A. Resistance may be produced by hyperproduction of beta-lactamase Methicillin resistance is expressed more at 30degC than at 37degC. Therefore, resistance may be missed at incubation temperature at 37degC during susceptibility testing.