Which Genre was published by Atari and developed by NuFX in 1991?
CREATE TABLE "licensed_titles" (
  "title" text,
  "year" real,
  "developer" text,
  "publisher" text,
  "players_per_console" text,
  "genre" text
);
SELECT "genre" FROM "licensed_titles" WHERE "publisher"='atari' AND "year"=1991 AND "developer"='nufx';