Why Did Athens Attract More Sophists Than Other Similarly Sized

Why did Athens attract more Sophists than other similarly sized Greek city-states?

A) The demand was greater in Athens, since aspiring politicians needed the training in rhetoric that the Sophists offered to advance in Athens's democracy.
B) Other city-states, most notably Sparta and Corinth, banned Sophists from their territories, since the Sophists' teaching did not fit into the military education that those states emphasized.
C) The demand was greater in Athens, since the Athenian state preferred to hire Sophists to teach teenage boys rather than expanding its public school system to include boys in that age group.
D) The demand was greater in Athens, since Athenian women were denied a public education and had to rely on the services of tutors instead.