How many letters does the top answer for “from which country did the song gangnam style originate from” have?

The most common answer is korea (5 letters).

Crossword clue: from which country did the song gangnam style originate from

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

korea 5 letters otdb

an Asian peninsula (off Manchuria) separating the Yellow Sea and the Sea of Japan; the Korean name is Dae-Han-Min-Gook o

south 5 letters otdb

the region of the United States lying to the south of the Mason-Dixon line