According to TEXT C the difference between the East and West...

The West epitomizes individualistic, do-your-own-thing cultures, ones where the rights of the individual equal and often trump those of the group and where differences are valued. East Asian societies exalt the larger society; behavior is constrained by social roles, conformity is prized, outsiders shunned. […] But the reason a society falls where it does on the individualism-collectivism spectrum has been pretty much a mystery. Now a team of researchers has come up with a surprising explanation: disease-causing microbes. Societies that evolved in places with an abundance of pathogens, they argue, had to adopt behaviors that add up to collectivism, for reasons of sheer preservation. Societies that arose in places with fewer pathogens had the luxury of individualism, which is less effective at limiting the spread of disease but brings with it other social benefits, such as innovation. […]

    How might pathogen-fighting customs and attitudes arise, or fail to? Maybe people make conscious efforts to act in ways that inhibit the spread of pathogens, such as by shunning strangers and demanding conformity. Or maybe there are genes for behaviors that, at the level of a whole society, manifest themselves as collectivism or individualism, and genes for individualism get wiped out in diseaseplagued regions. But when East Asians move to the West or Westerners go East, […] they begin to see, think and behave like people in their adopted society. That would be hard to do if they were in the grip of collectivist or individualistic genes. The presence of pathogens also predicts cross-cultural differences in personality traits, not just shared cultural values. […] The physical world has shaped skin color and other superficial features. The next frontier is fathoming how it might have shaped our very thoughts and values. 

Sharon Begley, Newsweek, April 14th, 2008