Which of the following CREATE TABLE statements will NOT be successful?

Which of the following CREATE TABLE statements will NOT be successful?

A.
CREATE TABLE t1 (c1 XML NOT NULL UNIQUE, c2 INT)

B.
CREATE TABLE t1 (c1 XML NOT NULL, c2CHAR(20))

C.
CREATE TABLE t1 (c1 XML CHECK (c1 IS VALIDATED), c2 INT)

D.
CREATE TABLE t1 (c1 XML, c2 XML)