Why Is Jupiter the Largest Planet in the Solar System

Why is Jupiter the largest planet in the solar system?

A) because that's just the way it happened.
B) Being the oldest planetary core, it had more time than the other planets to accumulate enough gas around itself before solar winds blew interplanetary dust away.
C) due to a massive collision with another protoplanet
D) Because of its distance from the Sun, the gravitational attraction between it and the Sun is perfectly balanced so as to create a density that results in the largest size of any planet.