I take them all just for fun, and so should you.
I do.

These test make one-dimensional questions when the answers are often multidimensional (e.g. I support X if also Y is done, but if Y is not done I don't support X either, because it only makes sense with Y). The lack of multidimensional questions are made up having many one-dimensional questions and a simplistic algorithm tries to figure out how the person would have answered to fewer multi-dimensional questions.

Democratic Socialism - Social Democracy - Capitalism
What is the main difference, briefly, between these three?
So the USA is Capitalism and you are for Social Democracy? I thought Bernie was for Democratic Socialism.
Societies and economy are so complex systems, that the differences are hard to explain.
In
democratic socialism all or most means of production are owned by the people as a collective and how these means of production are run is decided democratically. This is the furthest right version of socialism and differs from socialism by having democratic process instead of the state telling what to do.
Social Democracy is the furthest left version of capitalism. It's build on capitalism, but also contains strong wellfare programs and many things are run by the state instead of private sector or together with private sector with heavy regulation (e.g. healthcare).
In
Capitalism it is thought that poverty is a failure of the individual rather than the society and wellfare programs are kept minimal as an insentive to try harder and succeed in life. Those who do succeed can gain extreme wealth.
Hopefully this clarifies there terms a little bit for you, but be aware that these terms aren't defined that well and people may disagree about details, but this is more or less how I define them.
The US is not pure idealistic capitalism. It's
crony capitalism. If the US was capitalistic, Exxon Mobile would not get $4 billion of subscidies each year just because it has bought the politicians to make it so. Legal bribery in the US makes the country crony capitalism aka
corporate socialism.
Bernie Sanders calls himself a Democratic Socialist, but he has the terminology
wrong. His political agenda is to advocate Social Democracy, the system used in countries like Denmark, Norway, Sweden and Finland which has empirically been very successful.