Explanation:
There is an electrostatic force holding the electrovalent bonds together and they're usually structured, whereas in covalent, they are usually free and are only held together by a very weak intermolecular force
1) The process of keeping, feeding, taking care etc... of useful animals.
2)To cut wool off a sheep or another animal
3)The production of silk and rearing of silk worms for this purpose
Answer: The correct option is D.
Explanation: Nonmetallic minerals are the chemical elements from which no new product can be formed when they are melted. For Example: Sand, marble etc..
For the given options:
Option A: Wood is a type of cellulose and is not considered as a nonmetallic mineral resource.
Option B: Iron is an element because it is the smallest substance which cannot be broken down. It is not considered as a nonmetallic mineral resource.
Option C: Coal is a mixture of carbon compounds. This is very close to mineral but is an organic mineral because it contains carbon atom. Hence, it is not considered as a nonmetallic mineral resource.
Option D: Aggregate is formed by the collection of particles forming a whole mass. This is a non-metallic resource as it cannot form any new product.
Hence, the correct option is D.