CREATE TABLE table_49849 ("Res." TEXT, "Record" TEXT, "Opponent" TEXT, "Method" TEXT, "Round" TEXT, "Location" TEXT)

What was the method of resolution when Mikhail Ilyukhin's record was 4-0?
SELECT "Method" FROM table_49849 WHERE "Record" = '4-0'
SELECT "Method" FROM "table_49849" WHERE "Record" = '4-0'