Neither of these are minerals, B.
Its not A because, they are not natural materials but instead made up of natural materials, like a rubber tree.
Its not C because, like I said, plastic is made from rubber trees, this garentees it doesnt have a crystal structure.
Its not D because, concrete is not a mineral and has indefinite composition.
Answer:
D
Explanation:
Comets are brightest near the sun.
Fog begins to form when water vapor condenses into tiny liquid water droplets that are suspended in the air.
