CREATE TABLE table_31668 ("Year" CLOB, "Competition" CLOB, "Opponent" CLOB, "Score" CLOB, "Venue" CLOB)

At the VFL Reserves, who was the opponent when the score was 18.6 (114) - 21.14 (140)?
SELECT "Opponent" FROM table_31668 WHERE "Competition" = 'vfl reserves' AND "Score" = '18.6 (114) - 21.14 (140)'
SELECT "Opponent" FROM "table_31668" WHERE "Competition" = 'vfl reserves' AND "Score" = '18.6 (114) - 21.14 (140)'