Phèn crom - kali có công thức nào sau đây?

A. \({{\text{K}}_{2}}\text{S}{{\text{O}}_{4}}\text{.CrS}{{\text{O}}_{4}}.24{{\text{H}}_{2}}\text{O}.\)

B. \(\text{KCr}{{\left( \text{S}{{\text{O}}_{4}} \right)}_{2}}.24{{\text{H}}_{2}}\text{O}\text{.}\)

C. \({{\text{K}}_{2}}\text{S}{{\text{O}}_{4}}\text{.C}{{\text{r}}_{2}}{{\left( \text{S}{{\text{O}}_{4}} \right)}_{3}}.12{{\text{H}}_{2}}\text{O}\)

D. \({{\text{K}}_{2}}\text{S}{{\text{O}}_{4}}\text{.C}{{\text{r}}_{2}}{{\left( \text{S}{{\text{O}}_{4}} \right)}_{3}}.24{{\text{H}}_{2}}\text{O}\)