The price of a European call option on a non-dividend-paying stock with a strike price of ¥50 is ¥6. The stock price is ¥51, the continuously compounded risk-free rate (all maturities) is 6% and the time to maturity is one year. What is the price of a one-year European put option on the stock with a strike price of ¥50?  
A、¥9.91
B、¥7.00
C、¥6.00
D、¥2.09