Which planet formed near the sun where the solar stems temperatures were very high? Jupiter, mars, Neptune, Saturn

Mars is your best answer

Except for the case of Venus (which is the hottest planet of our solar system because of the resources it is made of), temperature vary depending on how close the planet is to the sun. The farther it is (Mars, Neptune, Jupiter, Saturn, respectively in order), the colder it is (if the planet leans towards the right).

~Rise Above the Ordinary