ABC Inc., a publicly traded company, 100,000 granted stock options on January 1, Year 1, with a total value of $150,000. The option will vest over a 3-year period, and employees may exercise their options as of year 4. On December 31, Year 1, it is estimated that 80% of the options will fully vest. During Year 2, an executive suddenly quit, forfeiting 20,000 options. On December 31st, Year 2 the estimate of the number of options that will fully vest by the end of Year 3 was revised to 50,000. The December 31st, Year 2 year-end accrual required with respect to these stock options would include a compensation expense amount of:

a. answer not provided

b. 10,000

c. 20,000

d. 25,000

e. 30,000