Answer:
Neptune
Step-by-step explanation:
In the solar system, there are 8 planets. The arrangement of planets in order from closest to farthest from sun is:
Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
The planets revolve around Sun in elliptical orbit. The planet closest to the sun would have smallest orbital radius and the planet farthest from the sun would have largest orbital radius. Thus, Neptune which is the last planet of the solar system has the largest orbital radius.