IMO C.. it maintains the parallelism..

A IMO. Nothing's wrong with the sentence.

i vote A me hearties!!

we need simple past all throughtout IMO so the options with "making" need to be dropped.

surely it is B

IMO A is best because.

A. Approved April 24, 1800, the act of Congress that made provision for the removal of the government of the United States to the new federal city, Washington, D.C., also established
Correct.

B. The act of Congress, which was approved April 24, 1800, making provision for the removal of the government of the United States to the new federal city, Washington, D.C., also established
making is wrong tense..this is comma + ing setup...should modify the previous clause.....but as such there is no previous clause....moreover if it modifies.....which was approved....then it non sensically say that during the time of approval.....provision was made.

C. The act of Congress approved April 24, 1800, which made provision for the removal of the government of the United States to the new federal city, Washington, D.C., and established
and established parallel to what ? Approved and established are not simulataneous actions....established has to follow approved....

D. Approved April 24, 1800, making provision for the removal of the government of the United States to the new federal city, Washington, D.C., the act of Congress also established
Approved modifies making......it should modify the "act"

E. Approved April 24, 1800, the act of Congress made provision for the removal of the government of the United States to the new federal city, Washington, D.C., also establishing
establishing has no parallel element.