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B is corrent. The lifetime learning credit provides a credit of 20% of up to $10,000 of tuition and fees paid by a taxpayer for one or more students for graduate and undergraduate courses at an eligible educational institution. The credit may be claimed for an unlimited number of years, is available on a per taxpayer basis, and covers tuition and fees paid for the taxpayer, spouse, and dependents.
A is incorrect because the credit is available for an unlimited number of years. 
C is incorrect because the credit is available for an unlimited number of years.
D is incorrect because the credit is available for an unlimited number of years.