A Solution Contains 40 Mg/cm³ of Pure Protein at 150 $\times$

A solution contains 40 mg/cm³ of pure protein at 150 Pa and 300 K. The molar mass of the protein is

A) 1 u.
B) 1.7 u.
C) 6.6 u.
D) 1.7 $\times$ 10⁵ u.
E) 6.6 $\times$ 10⁵ u.