Section 38I. In determining the net income subject to tax under this chapter for the taxable year, a business corporation may deduct in addition to any other allowable deduction under this chapter, a deduction equal to the credit allowed under section fifty-one of the Federal Internal Revenue Code as amended and in effect for the taxable year, with respect to wages deemed to be compensation paid in the commonwealth within the meaning of subsection (e) of section thirty-eight of this chapter; provided, however, that with regard to compensation qualifying for this deduction and the deduction under section thirty-eight F of this chapter, the corporation may elect either of two deductions but not both. Any such election must be made annually on the return filed and shall be irrevocable.