Which of the following statements is true, all else equal? For both calls, and puts an increase in the exercise price will cause an increase in the option price. For calls an increase in the interest rate will cause an increase in the option price. For both calls and puts, an increase in the time to expiration will cause an increase in the option price. For puts, but not calls, an increase in the time to expiration will cause an increase in the option price. Both b and c