When should you use Java IDL and when should you use RMI-IIOP?

a. You should use Java IDL when using Enterprise Java Beans.
b. You should use RMI-IIOP when using Enterprise Java Beans.
c. You HAVE to use RMI-IIOP when using Enterprise Java Beans.
d. Java IDL can be used even if the remote interfaces were originally defined as RMI interfaces.
e. RMI-IIOP can be used with CORBA only if the remote interfaces were originally defined as RMI interfaces.
f. RMI-IIOP can be used with CORBA even if not all of the remote interfaces were originally defined as RMI interfaces.
g. It comes down to programmer preference as both can be used in all situations.