This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteria, Subject name: Microbiology
Organism causing IV biofilm? 
Select and explain. 
A. Staph epidermis, B. Acinetobacter baumannii, C. Meningococci, D. Mycobacterium
A: Staph epidermis
Answer: A: Staph epidermis 
Explanation: Ref: Harrisons, 19th ed. pg. 145e-4* Many bacterial, fungal, and protozoal species have the ability to grow in multicellular masses called biofilms.* These masses are biochemically and morphologically quite distinct from the free-living individual cells referred to as planktonic cells.* Growth in biofilms leads to altered microbial metabolism, production of extracellular virulence factors, and decreased susceptibility to antimicrobial agents, biocides, and host defense molecules and cells.* Examples of bacterial organisms forming biofilm:# P. aeruginosa, staphylococci and other pathogens growing on implanted medical devices, and dental pathogens growing on tooth surfaces to form plaque# S. epidermis - on Prosthetic valve, IV catheter# Strep Mutans/sanguinis - on Dental plaques# Pseudomonas - Cystic fibrosis, contact lens# Strep, viridans - Endocarditis# Non-typable H. influenza Otitis. Media