Which of the following best describes the structure of diamond?

The correct option is A lattice of carbon atoms with four covalent bonds per atom. This answer is correct because it matches the approved learning objective to identify diamond, graphite and silicon dioxide as examples of giant covalent structures in the subtopic Giant covalent structures.

The correct option is A lattice of carbon atoms with four covalent bonds per atom. A lattice of carbon atoms with four covalent bonds per atom is correct because it directly supports the approved learning objective to identify diamond, graphite and silicon dioxide as examples of giant covalent structures. This belongs to the subtopic Giant covalent structures within How bonding and structure are related to the properties of substances, so the explanation must stay tied to that curriculum context. The other options are incorrect because they either do not answer this learning objective, use a vague statement, or move away from Giant covalent structures.