Contaminated hospital equipment represents a difficult environment to control harmful microbial growth. Regarding influences that affect disinfection of hospital equipment, which of the following is an accurate statement?

"Contaminated hospital equipment represents a difficult environment to control harmful microbial growth. Regarding influences that affect disinfection of hospital equipment, which of the following is an accurate statement?

Biofilms are extracellular matrix formed by organisms. They are slimy and are used to attach to surfaces. They are made of polysachharides and form a barrier of protection against disinfectants. Therefore, they make it difficult to decontaminate surfaces.

Organic matter like dried blood or protein also affect the action of antimicrobial agents. Organic matter may form a layer that would reduce the access of the disinfection to the organism.

Antimicrobial agents are affected by temperature and have optimum temperature of action. Some get denatured by heat while some are unaffected. The temperature an antibiotic works will also depend on the organism and its mode of action.  

Gram negative bacteria have shown resistance to more antimicrobials.