Answer: I a reference to the next node
III a data element
Explanation:
A linked list is simply referred to as a linear data structure, whereby the elements would not be stored at memory locations that are together in the sequence.
In simple words, we can simply say that a linked list is made up of nodes in which, every node has a data element and also a link or reference to the next node that is in the list.
Therefore, based on the explanation above, the correct option will be:
I. a reference to the next node
III a data element