Passage: The issue of how to structure Congress was one of the most divisive among the founders during the Convention. Edmund Randolph's Virginia Plan called for a bicameral Congress: the lower house would be "of the people", elected directly by the people of the United States and representing public opinion, and a more deliberative upper house, elected by the lower house, that would represent the individual states, and would be less susceptible to variations of mass sentiment.The House is referred to as the lower house, with the Senate being the upper house, although the United States Constitution does not use that terminology. Both houses' approval is necessary for the passage of legislation. The Virginia Plan drew the support of delegates from large states such as Virginia, Massachusetts, and Pennsylvania, as it called for representation based on population. The smaller states, however, favored the New Jersey Plan, which called for a unicameral Congress with equal representation for the states.Eventually, the Convention reached the Connecticut Compromise or Great Compromise, under which one house of Congress (the House of Representatives) would provide representation proportional to each state's population, whereas the other (the Senate) would provide equal representation amongst the states. The Constitution was ratified by the requisite number of states (nine out of the 13) in 1788, but its implementation was set for March 4, 1789. The House began work on April 1, 1789, when it achieved a quorum for the first time.

Question: Who must approve legislation for it to pass?
Both houses'