What is the common characteristic of bactericidal agents?

Bactericidal agents are specifically designed to kill bacteria, making this characteristic their defining feature. Unlike bacteriostatic agents, which only inhibit bacterial growth and reproduction, bactericidal agents actively destroy the microorganisms. This ability to eliminate bacteria is critical in various settings, such as healthcare, where controlling bacterial infections and limiting their spread is essential.

The other choices do not represent the function of bactericidal agents: promoting growth of bacteria contradicts the agent's purpose; only inhibiting bacteria does not mean the bacteria are killed, and enhancing pathogenicity is unrelated to the role of bactericidal agents, which focus on eradication rather than promoting harmful effects.