Which city has a C1 class and Identifier of CBCD-FM?
CREATE TABLE "s_rebroadcaster_of_cbo_fm" (
  "city_of_license" text,
  "identifier" text,
  "frequency" text,
  "power" text,
  "class" text,
  "rec_net" text
);
SELECT "city_of_license" FROM "s_rebroadcaster_of_cbo_fm" WHERE "class"='c1' AND "identifier"='cbcd-fm';