Question

section one
matching
sphere of influence\troosevelt corollary\tpan-americanism
anglo - saxonism\twilliam crawford gorgas\tyellow journalism
platt amendment\tforaker act\tprotectorate
dollar diplomacy

section two
multiple choices
japanese trade w/u.s.\tu.s. world power\tsensational stories
pan - american conference\tspanish - american war\ttreaty of paris 1898
annexation\topen - door policy/china\tpanama canal
mexico/woodrow wilson

Explanation:

The problem involves historical terms and events related to U.S. history (e.g., Platt Amendment, Spanish - American War, Roosevelt Corollary), so the subfield of History (under Social Science) is the most applicable.

Answer:

The subfield is History (under Social Science).