Why do hurricanes initially form only in the tropics?

The warm winds are in the south part of the planet and the cold winds are in the northern part of the earth. When the northern winds change their direction south and the warm winds change their direction north, they meet and the clashing of extreme temperatures creates the perfect conditions for hurricanes to form.

The sun's parallax would be 180 degrees, greater than which you can't get.  so a. would be your anwser