Question
When was the first professional baseball league founded in the United States?
Responses
1831
1831
1871
1871
1931
1931
1971
Responses
1831
1831
1871
1871
1931
1931
1971
Answers
GPT-4o mini
The first professional baseball league founded in the United States was the National Association of Professional Base Ball Players, which was established in 1871. So the correct response is **1871**.