What do beta-lactam antibiotics like penicillin inhibit in bacteria?

Beta-lactam antibiotics, such as penicillin, specifically inhibit cell wall synthesis in bacteria. Bacterial cell walls are primarily composed of peptidoglycan, which provides structural integrity and protection. Penicillin works by binding to and inhibiting enzymes known as penicillin-binding proteins (PBPs), which are essential for the cross-linking of peptidoglycan layers. When these enzymes are inhibited, the bacteria are unable to properly build their cell walls, leading to cell lysis and ultimately bacterial death.

While other options address important cellular processes, they are not the primary target of beta-lactam antibiotics. For example, options that mention RNA synthesis, protein production, and DNA replication involve different mechanisms and targets within the bacterial cell. The effectiveness of beta-lactam antibiotics hinges on their ability to disrupt the cell wall's structural integrity, making option C the correct choice.