Evaluate the following statements：  
CREATE TABLE purchase_orders （po_id NUMBER（4）， 
po_date TIMESTAMP， supplier_id NUMBER（6）， po_total NUMBER（8，2）， 
CONSTRAINT order_pk PRIMARY KEY（po_id）） PARTITION BY RANGE（po_date） 
（PARTITION Q1 VALUES LESS THAN （TO_DATE（？1-apr-2007？d-mon-yyyy？）， PARTITION Q2 VALUES LESS THAN 
（TO_DATE（？1-jul-2007？d-mon-yyyy？）， 
PARTITION Q3 VALUES LESS THAN（TO_DATE（？1-oct - 2007？d-mon-yyyy？）， PARTITION Q4 VALUES LESS THAN （TO_DATE（？1-jan-2008？d-mon-yyyy？））； 
CREATE TABLE purchase_order_items （po_id NUMBER（4） NOT NULL， product_id NUMBER（6） NOT NULL， unit_price NUMBER（8，2）， quantity NUMBER（8）， CONSTRAINT po_items_fk FOREIGN KEY 
（po_id） REFERENCES purchase_orders（po_id）） PARTITION BY REFERENCE（po_items_fk）；  
What are the two consequences of the above statements？（）

A. Partitions of PURCHASE_ORDER_ITEMS have system-generated names.
B. Both PURCHASE_ORDERS and PURCHASE_ORDER_ITEMS tables are created with four partitions each. 
C. Partitions of the PURCHASE_ORDER_ITEMS table exist in the same tablespaces as the partitions of the PURCHASE_ORDERS table.
D. The PURCHASE_ORDER_ITEMS table inherits the partitioning key from the parent table by  automatically duplicating the key columns.
E. Partition maintenance operations performed on the PURCHASE_ORDER_ITEMS table are automatically reflected in the PURCHASE_ORDERS table.