The challenges of democracy and ways​

1) Overcoming polarization

2) Immigration and the challenge of sustaining multiethnic democracies

3) Globalization, economic inequality, and democratic discontent

4) The causes of populism and its consequences for democracy

5) Debates over institutional solutions

Explanation:

the fact that could also be added to column b is that during world war ii, specifically between the years 1941 and 1945, japan expanded its territory towards the indonesian territory in what was known later as part of the "pacific war". in that time, japan could conquer the philipines, singapore,   borneo, central java, malang, cebu, sumatra and various other islands of the area, therefore expanding its territory for a brief period of time.