Though no longer a series of colonies, the united states retains close ties to britain as
a. a commonwealth
b. a dependency
c. a dominion
d. part of a “special relationship”

Though no longer a series of colonies, the United States retains close ties to Britain as d) part of a "special relationship." Many of the former colonies of Great Britain are commonwealths or dominions or some generally depend on Britain for a set of purposes, but the United States is not one of them. However, the United States often is side by side in political decisions with Great Britain and shares linguistic ties with their neighbor across the Atlantic.