C) 1
Explanation
to solve this we need to convert from miligrams to grams, to do that, itiis necesary to know the equivalence
[tex]1\text{ gr = 1000 miligrams}[/tex]so
[tex](\frac{1\text{ gra}}{1000\text{ miligrams}})=1[/tex]this way we can multiply the amount ( in miligrams ) by the fraction
hence
[tex]\begin{gathered} 1000\text{ miligrams}\Rightarrow1000\text{ miligrams(}\frac{1\text{ gr}}{1000}\text{)}=1\text{ gram} \\ so \\ \text{the answer is 1 gram} \end{gathered}[/tex]C) 1
I hope this helps you