Taxpayer submits a timely extension request for their 2019 Form 1040 (on April 15, 2020). The Form 1040 is filed on June 1, 2020. The Form 1040 shows a balance due of $500. The balance is not paid until July 1, 2020. The statute of limitations for this return expires on: a. April 15, 2023. b. June 1, 2023. c. July 1, 2023. d. October 15, 2023. e. None of the above.