An individual who is a part-year resident of South Carolina may:
(1) report and compute South Carolina tax as if the individual was a resident for the entire year and use the credit provided in Section 12-6-3400; or
(2) report and compute South Carolina tax as a nonresident individual as provided in Section 12-6-1720, except that for purposes of this computation, South Carolina taxable income for that period during which the individual was a resident includes all items of income, gain, loss, or deductions that a resident would be required to include under Section 12-6-560.