Scientists Believe That Approximately 60 Million Years Ago the Closing

Scientists believe that approximately 60 million years ago the closing of the Isthmus of Panama changed the climate of Earth so severely that winters in Europe became 10°C warmer than they had been.Why did this happen?

A) Cold Caribbean Sea waters were forced up into the north Atlantic Ocean.
B) Warm Caribbean Sea waters were forced up into the north Atlantic Ocean.
C) The ice in the Caribbean Sea was broken apart by plate movements.
D) A mountain range formed that blocked the movement of cold air into the area.