What is the primary function of an antibiotic?

The primary function of an antibiotic is to inhibit the growth of microorganisms, particularly bacteria. Antibiotics achieve this by targeting specific cellular processes in bacteria, such as protein synthesis, cell wall synthesis, or nucleic acid synthesis, effectively preventing them from multiplying and causing infections. This action can either kill the bacteria (bactericidal) or stop their growth (bacteriostatic), allowing the body's immune system to eliminate the remaining pathogens more effectively. This is critical in treating bacterial infections and preventing the spread of illnesses caused by these microorganisms.

The other options describe functions that are not associated with antibiotics. For example, enhancing the growth of microorganisms or promoting viral infections is contrary to the purpose of antibiotics, as they are specifically designed to combat bacterial infections, not to support microbial or viral proliferation. Destroying the body's immune cells would compromise the body's defenses against infections, which is also not related to the function of antibiotics.