Oracle: How to update using select.

UPDATE TABLE A
12 SET (A.address_1,
13 A.address_2,
14 A.address_3,
15 A.city,
16 A.state_code,
17 A.country_code,
18 A.zip,
19 A.zip_4) =
20 (SELECT ADDRESS_1, ADDRESS_2, ADDRESS_3, CITY, STATE_CODE, COUNTRY_CODE, ZIP, ZIP_4 FROM TABLE B
21 WHERE account_nbr=A.account_nbr AND ROWNUM =1)
22 WHERE EXISTS (SELECT 1 FROM TABLE B CCA WHERE CCA.account_nbr = TABLE A.account_nbr);