The Cabinet's role is to advise the President on any subject he may require relating to the duties of each member's respective office. The tradition of the Cabinet dates back to the beginnings of the Presidency itself.
rule of law is simply the guarantee that those in power shall be guided by the spirit of the constituion while making decisions and in their actions. It is the first foundation of the USA constitution calling on all entities, and indiduals in The USA to be accountable to the laws of the land. in the american government, leaders are expected to follow the spirit of the law while making decisons. For example the president ensures that he respect the separation of power doctrine.
D) Writing letters to state representatives is the most applicable in this situation as road infrastructure is run by the state government.