Article i, section 9 “no preference shall be given by any regulation of commerce or revenue to the ports of one state over those of another: nor shall vessels bound to, or from, one state, be obliged to enter, clear, or pay duties in another.”
according to the passage, the constitution limits federal power by
a. prohibiting the federal government from taxing foreign imports.
b. allowing federal preferences of one state's ports over another.
c. preventing federal taxes on goods moving from state to state.
d. keeping vessels from moving from state to state.