According to the Text,all of the Following Are Challenges Faced

According to the text,all of the following are challenges faced in implementing a sampling design in international research EXCEPT:

A) individuals responsible for making or influencing decision may vary.
B) in developing an appropriate sampling frame one cannot rely on high-quality secondary data as one can in developed countries.
C) equivalence of samples can elude the researcher.
D) probability sampling techniques are uncommon overseas.
E) non-governmental organizations are needed for implementing the sampling design in some countries of the world.