A common mechanism by which certain bacterial pathogens, such as Streptococcus pneumoniae and Haemophilus influenzae, evade phagocytosis and contribute to their virulence is the production of which structural component?

✓ Correct Answer: Option C

Bacterial capsules are composed of polysaccharides and act as a protective layer that inhibits phagocytosis by host immune cells like macrophages and neutrophils, thereby enhancing bacterial survival and virulence.