Triple

Target entity: Missouri–Texas main line
Context triple: [Missouri–Kansas–Texas Railroad, notableRoute, Missouri–Texas main line]

• A. Missouri–Kansas–Texas Railroad chosen
  The Missouri–Kansas–Texas Railroad, commonly known as the MKT or "the Katy," was a major American railroad that served the south-central United States, particularly linking Missouri, Kansas, Oklahoma, and Texas.
• B. Colorado Central Railroad
  The Colorado Central Railroad was a 19th-century narrow-gauge railroad in Colorado that played a key role in serving the region’s mining communities and connecting mountain towns to larger rail networks.
• C. Pacific Railroad (Missouri)
  Pacific Railroad (Missouri) was one of the earliest major railroads in Missouri, playing a key role in developing rail transport from St. Louis westward in the mid-19th century.
• D. St. Louis–San Francisco Railway
  The St. Louis–San Francisco Railway, commonly known as the Frisco, was a major American railroad that operated in the central and south-central United States from the late 19th to the mid-20th century.
• E. Kansas Pacific
  "Kansas Pacific" is a 1953 American Western film starring Sterling Hayden, set during the Civil War and centered on efforts to build a strategic railroad line across Kansas.
• F. None of above.
• G. Unsure - the case is ambiguous/there is not enough information to decide.