$1.80 \ g$ of solute $A$ was dissolved in $62.5 \ cm^{3}$ of ethanol and the freezing point of the solution was found to be $155.1 \ K$. The molar mass of solute $A$ is $.......... \ g \ mol^{-1}$.
[Given: Freezing point of ethanol is $156.0 \ K$,Density of ethanol is $0.80 \ g \ cm^{-3}$,Freezing point depression constant of ethanol is $2.00 \ K \ kg \ mol^{-1}$]

• A
  $81$
• B
  $80$
• C
  $82$
• D
  $83$