In 2020, Peter received a $10,000 bonus from his employer. The $10,000 was included in Peter's 2020 taxable income. In 2021, Peter's employer determined that Peter should not have gotten a bonus, and Peter was forced to refund $10,000 to his employer. Under the claim of right doctrine, which of the following is correct?

Group of answer choices

Peter cannot take a deduction for the $10,000 refund.

Peter can take a miscellaneous itemized deduction for $10,000 in 2021.

Peter should file a Form 1040x for 2020 and claim an additional $10,000 miscellaneous itemized deduction

Peter can take a credit of $10,000 on his 2021 income tax return.