Which of the following is true regarding federal taxation? a. the u. s. constitution explicitly grants congress the power to tax. b. the taxes laid by congress must be uniform across the states. c. congress can legitimately use taxes to encourage the development of certain industries and discourage the development of others. d. the u. s. constitution explicitly grants congress the power to tax; the taxes laid by congress must be uniform across the states; and congress can legitimately use taxes to encourage the development of certain industries and discourage the development of others. e. none of these.