CREATE TABLE table_30161 ("Proceed to Quarter-final" TEXT, "Match points" TEXT, "Aggregate score" TEXT, "Points margin" FLOAT, "Eliminated from competition" TEXT)

Who proceeded to the quarter finals with a points margin of 21?
SELECT "Proceed to Quarter-final" FROM table_30161 WHERE "Points margin" = '21'
SELECT "Proceed to Quarter-final" FROM "table_30161" WHERE "Points margin" = '21'