A.IF條件1THEN語句[ELSEIF條件2THEN語句][ELSE 語句]END IFB.IF條件1THEN語句[ELSEIF條件2THEN語句][ELSE 語句]C.IF條件1語句[ELSEIF條件2THEN 語句][ELSE 語句]END IFD.條件1THEN語句[ELSEIF條件2THEN語句][ELSE 語句]END IF