D. To remove the first node in a nonempty singly linked list, with no dummy node, (a) move the successor reference in the head node one node forward: head.next = head.next.next; (b) set a reference pred to the predecessor of the node you want to remove, and set the successor of pred to the successor of the head (c) move the head reference one node forward: head head.next; td) delete the node by setting the head reference to null head null: E. For the implementation of a queue using singly linked nodes (a) front designates the first element and rear designates the last element; (b) rear designates the first element and front designates the last clement; (c) It does not matter, (a) and (b) would both lend to efticient implementations; (d) None of the above