What is the process to insert a new node in a linked list?

• A. Create the new node, set its data, and adjust the pointers of surrounding nodes.
• B. Delete the last node and reinsert.
• C. Directly append to the end using only the head pointer.
• D. Set the head pointer to the new node.

Answer: (A)

Inserting a new node in a linked list is about creating the node, storing its value, and then connecting it into the existing chain by updating the pointers around it. You make the new node, put the data in it, and then splice it between its predecessor and successor by adjusting the next pointers (and the previous pointers if it’s a doubly linked list). For example, if inserting after a given node, you set the new node’s next to that node’s old next and then make that node’s next point to the new node; in a doubly linked list you also set the new node’s prev to the given node and update the successor’s prev accordingly. If inserting at the head, you update the head to the new node and set its next to the old head; if at the tail, you link the old tail to the new node and update the tail. This is precisely what the described process covers: creating the node, assigning its data, and adjusting the surrounding pointers to keep the list intact. The other options describe actions that don’t correctly perform insertion—deleting and reinserting is unnecessary, appending without traversing or a tail reference isn’t guaranteed by using only the head, and merely setting the head pointer omits reconnecting the rest of the list.