A. INSERT INTO orders
VALUES (1,'10-mar-2007', 'direct',
(SELECT customer_id
FROM customers
WHERE cust_last_name='Roberts' AND
credit_limit=600), 1000);

B. INSERT INTO(SELECT o.order_id, o.order_date.o.orde_mode.c.customer_id, o.order_total FROM orders o, customers c WHERE o.customer_id = c.customer_id AND c.cust_last_name='Roberts'ANDc. Credit_limit=600) VALUES (1,'10-mar-2007', 'direct',(SELECT customer_id FROM customers WHERE cust_last_name='Roberts' AND Credit_limit=600), 1000);

C. INSERT INTO orders (order_id.order_date.order_mode,
(SELECT customer_id
FROM customers
WHERE cust_last_name='Roberts' AND
credit _limit=600) .order_total)
VALUES(1 ,'IO-mar-2007', 'direct', &customer_id, 1000);

D. INSERT INTO orders (order_id,order_date,order_mode,
(SELECT customer_id
FROM customers
WHERE cust_last_name='Roberts' AND
credit_limit=600) .order_total)
VALUES(1 ,'10-mar-2007', 'direct', &&customer_id, 1000);