Q: What layered form of carbon is used as a lubricant and in pencils?


Read this paragraph and choose the correct option from the provided answers:

Graphite is a form of carbon in which carbon atoms are arranged in layers. Bonds are strong between carbon atoms within each layer but relatively weak between atoms in different layers. The weak bonds between layers allow the layers to slide over one another. This makes graphite relatively soft and slippery. It is used as a lubricant. It also makes up the "lead" in pencils.

 Choices:

- carbonite

- copper

- lead

- graphite


A:
graphite