A Bicameral legislature

The Connecticut compromise provided for a bicameral legislature consisting of  a. an upper house and a lower house with one representing states, the other representing citizens in districts (wrong)

b. Co-equal houses with one representing states, the other representing citizens in districts

c. an upper house and a lower house with one representing states, the other representing citizens in states (wrong)

d. co-equal houses with one representing states, the other representing citizens in states