The last part of the declaration of independence contains a list of complaints the colonists has against king george. which of the following best describes an economic complaint the colonists has toward the king

You didn't give a list of choices, but I'm thinking the most likely economic complaint you are looking for is this:

Details:

In the Declaration of Independence, Thomas Jefferson provided a list of "facts to be submitted to a candid world" to demonstrate that the British king had been seeking to establish "an absolute Tyranny over these States" (the colonial states which were declaring their independence).  

Jefferson's list of complaints included items such as:

Cutting off trade as well as taxation complaints would both fall under economic concerns.  (The taxation concern was also especially about the issue of representation and a voice in government decisions.)

The various grievances listed in the Declaration were offered to support the colonies' position that tyranny was standard operating procedure by the British monarchy, and therefore the Americans were justified in establishing their independence from Britain.

b) the confederacy had to pay all union war expenses.