John was issued Incentive Stock Options (ISOs) in 2014, he exercised the options in 2016 and sold the stock in 2020. The options were issued when the stock was trading at $20 per share, he exercised the options at $50 per share and he sold the stock at $100 per share. What was his gain and what kind of tax did he pay?

$50 per share in long-term capital gain

$80 per share in long-term capital gain

$100 in ordinary income

$50 in ordinary income