Which XXX completes the prepend$()$ method in the Python LinkedList class for a singly$-$linked list?

def prepend$($self$,$ new$\_$node$)$:

if self.head $==$ None:

self.head $=$ new$\_$node

self.tail $=$ new$\_$node

else:

XXX

self.head $=$ new$\_$node

a$)$ self.tail $=$ new$\_$node

b$)$ self.head.next $=$ new$\_$node

c$)$ new$\_$node.next $=$ self.head

d$)$ new$\_$node $=$ self.head