You should keep the text the same passage as the original one, helping not only you but anybody coming here understand it better!
Your problem is only how to distingushish btw C and E, or how to eliminate E and choose C in a persuding way.
I dont remember the shape of the original text, but I want to separate the whole passage into the structure that I think will help you understand better:
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Many people believe that because wages are lower in developing countries than in developed countries,
competition from developing countries in goods traded internationally will soon eliminate large numbers of jobs in developed countries. Currently, developed countries' advanced technology results in higher productivity, which accounts for their higher wages. Advanced technology is being transferred ever more speedily across borders,
but even with the latest technology, productivity and wages in developing countries will remain lower than in developed countries for many years because developed countries have better infrastructure and better-educated workers. When productivity in a developing country does catch up, experience suggests that wages there will rise. Some individual firms in developing countries have raised their productivity but kept their wages (which are influenced by average productivity in the country's economy) low.
However, in a developing country's economy as a whole, productivity improvements in goods traded internationally are likely to cause an increase in wages. Furthermore, if wages are not allowed to rise, the value of the country's currency will appreciate, which (from the developed countries' point of view) is the equivalent of increased wages in the developing country. And although in the past a few countries have deliberately kept their currencies undervalued, that is now much harder to do in a world where capital moves more freely
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You see, in the first paragrahp, the author highlighs the belief of many people. What is that belief? See the blue colored.
In the same sentence, author attached with it the cause of that belief:
because wages are lower in developing countries than in developed countriesIn the second sentence, the author cited the cause of "lower wage": technology. But immediately he deny the role of technology by saying that technology can be tranfered through boderlines and consider another factor: better "infrastructure and better-educated workers"
In the second paragrahp, the author stops at and says many about the improvement in productivity. Finally, he claims that "
productivity improvements in goods traded internationally are likely to cause an increase in wages"
Clearly that, The author is evaluating what make many people think that "competition from developing countries in goods traded internationally will soon eliminate large numbers of jobs in developed countries"
I hope, with this analysis, you can find that C is correct.
E. This belief is not "well-known phenomenon"