Addition of 0.643 g of a compound to 50 mL of benzene (density = 0.879 g `mL^(–1)`), lowers the freezing points from 50.51ºC to 50.03C, If `K_f` for benzene is 5.12, the molecular mass of the compound is
| A. |
156.00 |
 |
| B. |
312.00 |
| C. |
78.00 |
| D. |
468.00 |