What is the economic, social, and political importance of oil

I assume you refer to petroleum, which as a fossil fuel, is a source of energy. Energy is needed to generate heat, to drive machines and to allow transport, for example when it is used as a fuel for planes.

The economic importance of oil is that energy is needed to produce all goods and oil or other sources of energy are indispensable: owning energy sources produces riches. The political importance is a result of this: politicians and powers are strong if they have a strong financial backup, and this can be provided by having access to an energy source. 
Similarly the social importance is based on the economical wealth oil brings: it allows for a development without financial fears for those who control it, but also creates differences based on wealth disparity.

Ithink the answer is d. the lower appellate and trial courts in the state.