<span>The Poverty threshold is the minimum level of income deemed adequate in a particular country. in general the poverty line is significantly higher in developed countries than in developing countries.In 2008 the World Bank fixed this at $1.25 at 2005 purchasing-power parity.
In the USA , for a single person under 65 the poverty threshold was an annual income of usd11,770 ; the threshold for a family of four including two children was USD 24,250.
But in October 2015 the same was revised to $1.90 at 2011 purchasing-power parity.</span>
Answer:
The answer to your question is B - Changes of economic structure.
