Which of the following activities does the Border Patrol address?

The Border Patrol primarily focuses on human trafficking and drug smuggling as part of its core mission to secure the nation's borders. These activities pose significant threats to national security and public safety. By combating human trafficking, the Border Patrol helps to protect vulnerable individuals from exploitation and abuse. Simultaneously, addressing drug smuggling is crucial for preventing illegal substances from entering the country, which can have devastating effects on communities.

While the other options may involve regulatory oversight or different agencies, they do not fall under the primary responsibilities of the Border Patrol. Legal fishing activities are typically managed by fisheries and wildlife authorities rather than border security. Environmental conservation efforts, although important, are generally handled by environmental protection agencies or non-governmental organizations focused on sustainability. Building infrastructure along the border is usually the responsibility of engineering and governmental bodies, rather than a task directly managed by the Border Patrol itself. Thus, the primary concern for the Border Patrol remains focused on human trafficking and drug smuggling, which directly relate to law enforcement and border security.