QUESTION 15 Trace a queue (called Q) through the following operations: Queue Q = new Queue(); 0.enqueue (new Integer (3)) Integer X Q.dequeue() ; Q.enqueue (ne Integer (12)) ?.enqueue {new Integer(5)); Q.enqueue(ne Integer(1)) Integer Y-?.first(); Q.enqueue (new Integer(9)): Q.enqueve (Q.dequeue )) Give the contents of the queue after the code has been executed. a-91 (front) O b. 9 1 5 (front) O c. 501 (front) O d. None of these