For the first question regarding Karl Marx's view of religion and society, the correct answer is:
Option D: Religion simply kept the Proletariat in their low social class.
Marx viewed religion as a tool used by the ruling class (Bourgeoisie) to pacify and control the working class (Proletariat), thereby perpetuating their domination.
For the second question about the yin-yang symbol, the correct answer is:
Option D: Taoism.
The yin-yang symbol is a fundamental aspect of Taoist philosophy and represents the dualities present in the universe.