Which two code fragments can be used on Line 22 to persist an order instance assuming that all references are properly initialized?

Given this Java EE application that uses a JTA application-managed entity manager:
20. UserTransaction utx = …;
21. utx.begin();
22. //insert code here

23. utx.commit();
Which two code fragments can be used on Line 22 to persist an order instance assuming that all
references are properly initialized? (Choose two.)

A.
em.merge(order);
em.flush();

B.
em.persist(order);
em.flush();

C.
em.joinTransaction();
em.persist(order);

D.
em = emf.createEntityManager();
em.persist(order);