What is the lowest against score for Twickenham, London with the status of Five Nations against Ireland?
CREATE TABLE "1948" (
  "opposing_teams" text,
  "against" real,
  "date" text,
  "venue" text,
  "status" text
);
SELECT MIN("against") FROM "1948" WHERE "venue"='twickenham, london' AND "status"='five nations' AND "opposing_teams"='ireland';