The grinding away of rock by another rock is called erosion.
Hey there,
D is probably your best bet here. It might be b, and sorry if it is but I'd go with d.
Hope this helped, have a great day :)
The author of the story is implicating that this person is a “hard lump of clay” or a “hard glinty coal” in the sentenc. Notice how in both of these examples they mention the word hard, and an object that is dull. They <em>could</em> be saying that this person was hard to befrend, talk to or whatever the content is and that they seem like a dull person.
For example, let’s call them Henry.
”Henry was a hard person to get to know, he was always very dull.”
