The price of a non-dividend paying stock is $55 per share. A 6-month, at the money call option is trading for $1.89. If the annual interest rate is 6.7%, what is the price, based on put-call parity, of a European put at the same strike and expiration?

a. $0.135

b. $0.56

c. $0.055

d. $0.88