CREATE TABLE table_43256 ("Season" CLOB, "Staffel A" CLOB, "Staffel B" CLOB, "Staffel C" CLOB, "Staffel D" CLOB, "Staffel E" CLOB)

What is the Staffel A that has a Staffel D of Energie Cottbus and a Staffel C of Chemie Leipzig and a Staffel B of 1. FC Union Berlin?
SELECT "Staffel A" FROM table_43256 WHERE "Staffel D" = 'energie cottbus' AND "Staffel C" = 'chemie leipzig' AND "Staffel B" = '1. fc union berlin'
SELECT "Staffel A" FROM "table_43256" WHERE "Staffel B" = '1. fc union berlin' AND "Staffel C" = 'chemie leipzig' AND "Staffel D" = 'energie cottbus'