Consider a doubly linked list and three nodes pointed by dnode* variables p, q, r. Assume the node pointed by q follows the one pointed by p and preceeds the one pointed by r. Which of the following statements delete the node pointed by q from the doubly linked list ?

	a.	p -> prev = q -> next; p -> next = q -> prev; delete q;
	b.	p -> prev = q -> prev; r -> next = q -> next; delete q;
	c.	p -> next = q -> prev; r -> prev = q -> next; delete q;
	d.	r -> prev = q -> prev; p -> next = q -> next; delete q;