Of the countries that were the world’s twenty largest exporters in 1953, four had the same share of total world exports in 1984 as in 1953. Theses countries can therefore serve as models for those countries that wish to keep their share of the global export trade stable over the years.
Premise: Of the twenty countries, 4 countries have same share of global exports in 1984 as they had in 1953.
Conc: These countries are models for those countries that wish to keep their share of the global export trade stable over the years.
Note that conclusion talk about the stability of exports over the years but premise only mention that 4 countries had same exports in just two years. The assumption here is that in the years between 1953 and 1984, exports of those countries remained stable. Since we are supposed to weaken the argument, we need to find an option that suggests that exports were not stable in the years between 1953 and 1984.
Lets do the POE.
Which of the following, if true, casts the most serious doubt on the suitability of those four countries as models in the sense described?
(A) Many countries wish to increase their share of world export trade, not just keep it stable.
This is out of scope as we are only concerned about whether those 4 countries could keep their exports stable over the years as otherwise those countries cannot serve as model for other countries.
(B) Many countries are less concerned with exports alone than with the balance between exports and imports.
Similar to option A, this is also out of scope.
(C) With respect to the mix of products each exports, the four countries are very different from each other.
We are only concerned about those countries could maintain their share of total world exports over the years. The variation in the mix of products that they exported is not really a concern here. Eliminate.
(D) Of the four countries, two had a much larger, and two had a much smaller, share of total world exports in 1970 than in 1984.
This is correct as it points that in 1970 the share changed so those countries were actually not stable over the years so they cannot serve as model.
(E) The exports of the four countries range from 15 percent to 75 percent of the total national output.
This is incorrect as we are not concerned with the share percentage of those countries. We are only concerned with the stability of that share over the years.