Which of the following is true?

a. An executive gains on the exercise of stock options by the difference between the market price and the exercise price on the date of grant.

b. For an executive with stock options, a 2-for-1 stock split results in twice the number of options and half the exercise price.

c. Compensation cost for stock options used to be zero, because the company set the exercise price to be less than the market value on the date of grant.

d. The tax effects to the holder of the stock options dont differ between an incentive stock option plan and a nonqualified stock option plan.