Which CREATE TABLE statement is valid?

• A. CREATE TABLE ord_details (ord_no NUMBER(2) PRIMARY KEY, item_no NUMBER(3) PRIMARY KEY, ord_date date NOT NULL); 50
• B. CREATE TABLE ord_details (ord_no NUMBER(2) UNIQUE, NOT NULL, item_no NUMBER(3), ord_date date DEFAULT SYSDATE NOT NULL);
• C. CREATE TABLE ord_details (ord_no NUMBER(2) , item_no NUMBER(3), ord_date date DEFAULT NOT NULL, CONSTRAINT ord_uq UNIQUE (ord_no), CONSTRAINT ord_pk PRIMARY KEY (ord_no));
• D. CREATE TABLE ord_details (ord_no NUMBER(2), item_no NUMBER(3), ord_date date DEFAULT SYSDATE NOT NULL, CONSTRAINT ord_pk PRIMARY KEY (ord_no, item_no));