They are 4, Argentina, Brazil, Chile and Paraguay.
Explanation:
The tropic of Capricorn is an imaginary line is placed 23.5 degrees south of the Equator.
This is the zone where the sun is highest during the winter solstice, it was named around 2000 years ago by the Greeks. The word "troops", which means <em>turn</em>, because the sun seems to turn around in the opposite direction after every solstice.
