In 2018, an employee of a public corporation (Pubco) received a stock option to acquire 1,500 pubco shares at a price of $15 per share. The market price of the shares at that time was $18. In 2019, the employee exercised the option (purchased the shares) when the market price was $20. In 2020, the employee sold the shares at $24. What would be the employee's taxable capital gain in 2020? A. $3,000 B. $5,000 C. $4,000 D.$2,000