CREATE TABLE table_43817 ("Res." CLOB, "Record" CLOB, "Opponent" CLOB, "Method" CLOB, "Event" CLOB, "Round" CLOB)

What event was the opponent Karl Knothe and had a submission (rear naked choke)?
SELECT "Event" FROM table_43817 WHERE "Method" = 'submission (rear naked choke)' AND "Opponent" = 'karl knothe'
SELECT "Event" FROM "table_43817" WHERE "Method" = 'submission (rear naked choke)' AND "Opponent" = 'karl knothe'