Triple

Target entity: Soviet–Polish border conflicts
Context triple: [Ukrainian War of Independence, followedBy, Soviet–Polish border conflicts]

• A. Russo-Polish wars
  The Russo-Polish wars were a series of military conflicts between the Polish–Lithuanian Commonwealth (and later Poland) and the Russian state over territorial control and political influence in Eastern Europe from the 16th to the 20th century.
• B. Polish–Czechoslovak War
  The Polish–Czechoslovak War was a brief 1919 military conflict between the newly formed Second Polish Republic and Czechoslovakia over control of the disputed border region of Cieszyn Silesia.
• C. Polish–Soviet War chosen
  The Polish–Soviet War (1919–1921) was a major post–World War I conflict between the newly re-established Poland and Soviet Russia that helped determine the borders of Eastern Europe and the fate of the region’s independence movements.
• D. Polish–Lithuanian War
  The Polish–Lithuanian War was a post–World War I armed conflict between the newly re-established Second Polish Republic and the Republic of Lithuania over disputed border territories, particularly the Vilnius region, in 1919–1920.
• E. Polish–Ukrainian War
  The Polish–Ukrainian War was a 1918–1919 armed conflict between the newly re-emerging Polish state and Ukrainian forces over control of Eastern Galicia and its capital, Lviv, in the chaotic aftermath of World War I.
• F. None of above.
• G. Unsure - the case is ambiguous/there is not enough information to decide.