Answer:
(d) only rocky and metallic particles could form close to the Sun.
Explanation:
The Solar System form from a molecular cloud (compound by gas and dust), if there is a near perturbation to the cloud, maybe due to a supernova explosion, The molecular cloud will collapse under its own gravity, then, in some point start to rotate and will accrete all the material in a disk around the Protostar¹.
As a consequence of the gravitational force of the star, rocky and metallic particles will be more attracted to the inner part of the Solar System (close to the Sun) since they have more mass than the gas. That can perfectly explain the reason that all the inner planets are rocky and with metallic particles while the outer planets are gaseous.
An important fact is that when the star initiates thermal reactions in its core will be able to emit huge amounts of energy, what is better known as solar winds, these winds will expel more easily gas than the rocky and metallic particles from the Solar System.
All that was discussed above is know as the Nebular Theory, which is the better explanation until now for the formation of the Solar System.
Key term:
¹Protostar: A young star.
