His Britannic Majesty acknowledges the said United States . . . to be free, sovereign and independent States; that he treats with them as such; and for himself his heirs and successors, relinquishes all claims to the government, propriety and territorial rights of the same, and every part thereof. . . ." The conditions described in the excerpt most directly contributed to which of the following?
a. a harsh winter that decimated British troops
b. support given by the Hessians
c. foreign assistance from the French
d. a campaign of biological warfare by the Americans