Which termite baiting system provides localized reduction?

The correct choice highlights that ingesting toxicants in a termite baiting system leads to a localized reduction in termite populations. This method works by placing bait stations around the infested areas. When termites consume the bait, they ingest the toxicants that interfere with their growth or reproduction, and they may also carry these toxins back to their colony, affecting other termites. This targeted approach is effective in directly addressing the termites present in specific locations, thus helping to significantly reduce the population in those areas without spreading chemicals throughout the entire environment, which ensures a more controlled and efficient response to infestations.

In contrast, other options either do not provide the same level of targeted control or may not address the issue directly. For example, repellent chemicals create barriers but do not eliminate existing infestations effectively. Soil barriers offer a protective layer against termite entry but do not directly impact current infestations. Mechanical traps can capture termites, yet they do not inherently have a mechanism to affect the larger colony, making the bait with ingested toxicants the most effective for localized management of termite issues.