Political controversy about the public-land policy of the United States began with the America Revolution. (1) , even before independence from Britain was (2) , it became clear that (3) the dilemmas surrounding the public domain might prove necessary to (4) the Union itself.At the peace negotiation with Britain, Americans obtained a western (5) at the Mississippi River. Thus the new nation secured for its birthright a vast internal empire rich in agricultural and mineral resources. But (6) their colonial charters, seven states claimed (7) of the western wilderness. Virginia’s claim was the largest, (8) north and west to encompass the later states. The language of the charters was (9) and their validity questionable, but during the war Virginia reinforced its title by sponsoring Colonel Georgia Rogers Clark’s 1778 (10) to Vicennes and Kaskaskia, which (11) America’s trans-Appalachian pretensions at the peace table.The six states holding no claim to the transmontane region (12) whether a confederacy in which territory was so unevenly apportioned would truly prove what it claimed to be, a union of equals. Already New Jersey, Delaware, Rhode Isaland, and Maryland were (13) the smallest and least populous of the states. (14) they levied heavy taxes to repay state war debts, their larger neighbors might retire debts out of land-sale proceeds. (15) by fresh lands and low taxes, people would desert the small states (16) the large, leaving the former to fall (17) bankruptcy and eventually into political subjugation. All the states shared in the war effort, how then could half of them "be left no sink under an (18) debt, whilst others are enabled, in a short period, to (19) all their expenditures from the hard earnings of the whole confederacy" As the Revolution was a common endeavor, (20) ought its fruits, including the western lands be a common property. Read the following text. Choose the best word (s) for each numbered blank and mark A, B, C or D on ANSWER SHEET 1.4（）

A. ensure
B. maintain
C. preserve
D. remain