Which agency is part of Homeland Security and is responsible for protecting the nation's transportation systems and supervising entry of people and goods into the US?

• A. Federal Aviation Administration (FAA)
• B. National Transportation Safety Board (NTSB)
• C. Department of Homeland Security
• D. Transportation Security Administration (TSA)

Answer: (D)

The main idea here is recognizing the agency within Homeland Security that focuses on security across transportation networks. The Transportation Security Administration is the DHS component charged with safeguarding the nation’s transportation systems and carrying out security screening for travelers and their belongings. This includes airport screening, along with programs to secure other transportation modes, so it directly aligns with protecting how people and goods move through transportation channels.

Other options don’t fit as the primary focus: the Federal Aviation Administration regulates aviation safety but is part of the Department of Transportation, not Homeland Security; the National Transportation Safety Board is an independent investigative body, not a security agency within DHS; and the Department of Homeland Security is the parent department, not an individual agency.