问题详情

A recent study showed that more than 50 percent of people who commit violent crimes had seen at least one act of violence on television during the preceding week. Many psychologists suggest that exposure to acts of violence, even when they are obviously fictional, can increase a person"s propensity to commit violent acts. If government regulators were to ban all violence on television, therefore, we could expect the incidence of violent crimes to decrease by over 50 percent. The two portions in boldface in the passage above play which of the following roles？
A．The first portion is an inference related to the conclusion of the argument; the second portion supports the conclusion.
B．The first portion is a conclusion that is not necessarily true based on the evidence; the second portion supports that conclusion.
C．The first portion is evidence that supports the argument; the second portion is a conclusion that is not necessarily true based on the evidence.
D．The first portion is evidence that supports the argument; the second portion is a conclusion that must be true based on the evidence.
E．The first portion is a conclusion that must be true based on the evidence; the second portion is an inference related to that conclusion.