Which of the following statements concerning the Alternative Minimum Tax (AMT) system is correct?

a. A taxpayer who takes the standard deduction will not be required to calculate tax under the AMT.

b. Business-related expenses are never adjustment or preference items under the AMT.

c. A taxpayer exercising a large number of ISOs can avoid the AMT by selling the shares in the same tax year.

d. The AMT credit can be carried back for up to two years, then forward up to 5 years.