What has been the main cause in rapid rise of the human population in the 20th century?

the term is einsatzgruppen

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.