What social problems needed to be addressed in the united states in the late 19th century and early 20th century

the process of industrialization happened. so it may relate to that.  

Explanation:

the governor can not veto a referendum that the voters approve

the correct answer is d

a conference committee is a group of congress representatives appointed by the senate and the house to reach an agreement over a bill that had different versions in each chamber. this is due to the fact that, to pass a law. both the house and the senate must agree on the exact same content and wording of the bill to present it to the president.