What city was the center of ancient greek civilization

for (a) a tragedy was considered a main greek drama and it influenced alot of others. for (b) the actors in greek theater were named as aeschylus, sophocles, and euripides and sometimes playwrites. for (e) in a semi-circular theater called the "orchestra.". we'll the question was explain where the namer actors originated.

hope this : d

it the big letter b heart my answer