Which code, when added to the stateless session bean class, injects a container-managed persistence context at runtime?

A developer writes an enterprise application and packages it into an enterprise archive (EAR). The
application contains one persistence unit with unit name “FooPU”. The application also contains
an ejb-jar with one stateless session bean. Which code, when added to the stateless session bean
class, injects a container-managed persistence context at runtime?

A.
@PersistenceContext EntityManager em;

B.
@Resource(unitName=”FooPU”) EntityManager em;

C.
@PersistenceUnit(unitName=”FooPU”) EntityManager em;

D.
@PersistenceContext(unitName=”persistence/FooPU”) EntityManager em;