Which statement most closely describes how the polio vaccine works? a) it allows the blood to filter out the disease-causing agent. b) it prevents the disease-causing agent from entering the body. c) it attacks the disease-causing agent as soon as it enters the body. d) it triggers the immune system to produce antibodies to fight the disease-causing agent.

the sphincter muscles at the end of the digestive tract is the anus.

the framers of the constitution insisted that federal judges be nominated instead of elected due to their desire to have judges above the shifting whims of the masses.

the hope, whether achieved or not, was that federal judges would only be beholden to the law and that by not having judges be elected, they would be protected if that law dictated an outcome that ran counter to popular opinion.