In 1998, more citizens from the country of Monrovia migrated from Monrovia to neighboring Abstania than during any prior year. In 1998, the number of reported violent crimes in Abstania increased dramatically over 1997. The unavoidable conclusion is that Monrovians who migrated from Monrovia to Abstania were responsible for this increase.the first assumption: there was no other reason that was responsible for increase of reported violent crimes.
the second assumption: the number of Monrovians in Abstania increased in 1998.
the third assumption: the ratio of reported violent crimes to unreported ones is the same during all period.
Which of the following statements, if true, would most seriously weaken the claim that Monrovians were responsible for the increase in violent crime in Abstania during 1998?
(A) Each year more violent criminals are apprehended in Abstania than in Monrovia. - irrelevant. we don't know populations of both countries to calculate ratio and to say that Monrovians are more criminal than citizens of Abstania
(B) During 1998 more violent crimes were reported in Abstania than in Monrovia. - irrelevant. there is no information about population of counties to make a right comparison
(C) In 1998 no Monrovians migrated from either Monrovia or Abstania to any country other than Monrovia or Abstania. - irrelevant.
(D) In 1998 the number of unreported violent crimes in Abstania increased as well. - irrelevant. Slightly strength arguments (the third assumption)
(E) In 1998 fewer Monrovians migrated from Monrovia to Abstania than from Abstania to Monrovia - ok. it destroys the second assumption.
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