In the following search function for a linked list (using the Node and NodePtr as defined in the text), why is there code to check if here is NULL?

NodePtr search(NodePtr head, int target)
{
nodePtr here = head;
if(here == NULL)
{
return NULL;
}
else
{
while( here->data != target && here->link != NULL)
{
here = here->link;
}
if(here->data == target)
{
return here;
}
else
{
return NULL;
}
}
}
a. the list may be empty
b. the list may be full
c. there is no reason for that code to be there
d. A and B

a. the list may be empty