Answer :
The example of elemental carbon is diamond and it is pure form of carbon. Thus, option A is correct.
What is elemental carbon?
Elemental carbon is pure form of carbon and it does not contain other elements and present in natural form. Due to this reason it is known as elemental.
In elemental form pure atoms are not attached to any other atom. Example is diamond which is allotrope of carbon in which there is only carbon atom attached to each other.
Methane and proteins are compounds consist of a combination of carbon and other elements and they are not come in category of elemental carbon.
Therefore,the example of elemental carbon is diamond and it is pure form of carbon. Thus, option A is correct.
Learn more about elemental carbon here:
https://brainly.com/question/15304687
#SPJ1
