Well the if you want to get real technical then the Native Americans are the ones who found america first (that we know of) Then Columbus "discovered" America on his voyage to look for another country.
(Also, if you are religious then the short answer is just God) lol
The word 'of' is a preposition, so your prepositional phrase would be C. of city life. This is because the preposition is directly connected to the object, which in this case is the sounds of the city.
