Http://www.oneandonlycampaign.org/safe_injection_practices
<span>A pearl is not a mineral because it is created artificially. It is a gemstone, not a mineral because it is a composite of mineral Aragonite and a protein compound which is called conchiolin. Pearls are formed by organic and living organisms which is preserved to become a gemstone.</span>
What type of coding are you trying to learn?
I think it is D
Hope my answer help
Sorry it is wrong