The weight of the diamond in expressed in
Carat
Explanation for correct option A:
Explanation for incorrect option B:
This is the higher unit of measurement Milligram.
Explanation for incorrect option C:
Gram is not the unit of measurement for diamond.
Explanation for incorrect option D:
Diamond is one of the allotropic forms of carbons, the weight of diamond is expressed in carats (1 carat = 0.2 grams).
Thus, the weight of diamond is expressed in carats (1 carat = 0.2 grams).