Therefore, (E) option is the correct answer.
The mineral calcite can be scratched by a copper penny but cannot be scratched by a fingernail because the hardness of calcite is 3 on Moh's scale.
What is Moh's scale?
Moh's scale of mineral hardness is an ordinal scale to determine the scratch resistance of a material through the ability of harder materials to scratch softer materials. To give numerical values to this physical property, minerals are ranked along the Moh's scale, which is composed of 10 minerals that have been given arbitrary hardness values. Disadvantage of the Moh's scale is that it is not linear; that is, each increment of one in the scale does not indicate a proportional increase in hardness.