Which department administers programs for building and maintaining interstate highways, railroads, and airports?

The department that administers programs for building and maintaining interstate highways, railroads, and airports is indeed the Department of Transportation. This department is responsible for ensuring a safe and efficient transportation system in the United States, which includes overseeing the development and maintenance of various transportation infrastructures such as highways, railroads, and airports.

The Department of Transportation plays a vital role in coordinating the federal government's efforts to improve and expand transportation networks to enhance mobility for people and goods. It also provides funding and regulatory oversight for transportation projects, ensuring they meet safety and performance standards.

Other options, while related to infrastructure, do not specifically focus on transportation projects. For example, the Department of Commerce primarily deals with economic growth and promotes job creation, but it does not manage transportation infrastructure directly. Urban Development typically involves planning and improving urban areas, yet it also does not have a primary focus on the responsibilities held by the Department of Transportation regarding transportation systems.