Why Is Income Inequality Data Unreliable in Developing Countries

Why is income inequality data unreliable in developing countries?

A) The relative lack of computers means that most forms of record keeping are impossible.
B) Less developed countries have larger underground economies than developed ones.
C) Poorly developed infrastructures mean that data systems within developing nations are not connected to outside economic agencies via the Internet.
D) Almost all developing economies have tightly controlled borders,preventing international economic auditors from entering the country.
E) The data maintained by the United Nations reflects only the 20 largest economies,as those are deemed most crucial to international stability.