A company granted its employees 100,000 stock options on January 1, Year 1. The stock options had a grant date fair value of $15 per option and a three-year vesting period. On January 1, Year 2, the company estimated the fair value of the stock options to be $18 per option. Assuming that the company did notgrant any additional options or modify the terms of any existing option grants during Year 2, what amount of share based compensation expense should the company report for the year ended December 31, Year 2?
选项：

A: $500,000
B: $600,000
C: $700,000
D: $800,000