When 20 g of naphthoic acid $$(C_{11}H_8O_2)$$ is dissolved in 50 g of benzene $$(K_f$$ = 1.72 K kg mol$$^{-1}$$), a freezing point depression of 2 K is observed. The van't Hoff factor (i) is

A

0.5

B

1

C

2

D

3