The amount of a taxpayer's general business credit for any tax year is limited to the amount by which the taxpayer's net income tax exceeds the greater of:

	a.	The taxpayer's tentative minimum tax for the tax year or 25 percent of the amount by which the taxpayer's net regular tax liability exceeds $25,000.
	b.	The taxpayer's tentative minimum tax for the tax year or 15 percent of the amount by which the taxpayer's net regular tax liability exceeds $25,000.
	c.	The taxpayer's alternative minimum tax for the tax year or 25 percent of the amount by which the taxpayer's net regular tax liability exceeds $15,000.
	d.	The taxpayer's alternative minimum tax for the tax year or 15 percent of the amount by which the taxpayer's net regular tax liability exceeds $15,000.