Which of the following payments by International Partners Inc., a Montana corporation, qualifies for the foreign-tax credit?

a. Income tax paid to Germany, covered by an existing treaty.

b. Income tax paid to Adagio, with which the United States has no income tax treaty.

c. Value-added tax paid to Largetto, with which the United States has no income tax treaty.

d. Oil-extraction tax paid to Tedesco, with which the United States has no income tax treaty.

e. Transportation tax paid to Santa Lucia, with which the United States has no income tax treaty. The tax is reduced dollar for dollar when International provides consulting services in designing Santa Lucia’s new bullet train system. This year, International incurred $ 1 million in taxes, but it earned a $ 600,000 reduction for its services.