You are trying to set up a JMS Session with a specified acknowledgment mode. You want the application that receives the message to explicitly take care of the acknowledgment. Which option represents a valid choice for the acknowledgment mechanism that you can use? (Choose the best answer.) 

Answer options:

A. AUTO_ACKNOWLEDGE
B. CLIENT_ACKNOWLEDGE
C. DUPS_OK_ACKNOWLEDGE
D. DEFAULT_ACKNOWLEDGE

B

With CLIENT_ACKNOWLEDGE the Session object relies on the application to call an acknowledge method on a received message. Once the method is called, the session acknowledges all messages received since the last acknowledge. Incorrect Answers: A: With CLIENT_ACKNOWLEDGE the Session object acknowledges receipt of a message once the receiving application method has returned from processing it. C: With DUPS_OK_ACKNOWLEDGE the Session object acknowledges receipt of a message once the receiving application method has returned from processing it; duplicate acknowledges are permitted. D: There is no acknowledge mode named DEFAULT_ACKNOWLEDGE. Reference: http://docs.oracle.com/cd/E12840_01/wls/docs103/jms/fund.html