Sentence Correction

Income in a single year is a very poor guide to income and wealth over even a few years, much less a lifetime; in the longer run, a tax on what people spend is therefore not much different than a tax on their income.
(A) than a tax on their income
(B) from a tax on what they earn
(C) than taxing income
(D) from the income tax
(E) than a tax on what people earn
which one is a correct idiom......