Assume a linked list contains following integers: -3, 2, x, 5, 8, x, 15 and the pointer head is pointing to the first node of the list. What will be the value of variable a after the following statements are executed: Node *curNode=head; while(curNode->getNext()!=NULL){ curNode=curNode->getNext(); } curNode->setItem(12); int a=0; curNode=head; while(curNode!=NULL){ a+=curNode->getItem(); curNode=curNode->getNext(); } Group of answer choices 24+2x 27+2x 12 x