The Freezing Point of a 0

The freezing point of a 0.0925 m solution of ammonium chloride was found to be -0.325°C. What is the actual van't Hoff factor for this salt at this concentration compared to the ideal one of 2? K_f(water) = 1.86°C/m

A) 1.89
B) 1.95
C) 1.90
D) 1.80
E) 1.97