Final answer:
Salt is a naturally occurring, inorganic solid with a definite chemical composition and a characteristic crystalline structure. Hence, d) is correct.
Step-by-step explanation:
A naturally occurring inorganic solid with an orderly crystalline structure and a definite chemical composition is salt (option d). Salt, also known as sodium chloride (NaCl), is a commonly found mineral that meets all the criteria mentioned in the question.
It is a solid, not composed of complex carbon molecules, has a specific chemical formula, and exhibits a crystalline structure.