You observe a $20 price for a non- dividend- paying stock. The PUT option has two periods to mature, the periodically compounded risk- free interest rate is 2%, the exercise price is $20, u = 1.25, and d = 0.72. Assume the option is European- style. Based on a two-period binomial tree model, the option value is closest to:

2.69

3.46

4.66

5.23