Jose could not find his log book that proved his vehicle expenses for 2017. Therefore, he did not deduct this expense on his timely filed 2017 return. What is the latest date he can file an amended return, corrected for his unclaimed expenses, to obtain a refund of taxes paid on his 2017 return?

April 18, 2018.

April 17, 2019.

October 15, 2019.

April 15, 2021.