The CUSTOMERS table has these columns:<br /> <img src="https://nimg.ppkao.com/2018-08/yiyu/2018080116181325145.jpg?sign=b5a8264b8d72ad74cd37e607b914a456&t=62d355a2" /><br /> Which statement finds the rows in the CUSTOMERS table that do not have a postal code?()
A、SELECT customer_id, customer_name FROM customers WHERE postal_code CONTAINS NULL;
B、SELECT customer_id, customer_name FROM customers WHERE postal_code = '________';
C、SELECT customer_id, customer_name FROM customers WHERE postal_code IS NULL;
D、SELECT customer_id, customer_name FROM customers WHERE postal code IS NVL;
E、SELECT customer_id, customer_name FROM customers WHERE postal_code = NULL;