Which among the following is the only osmoconformer vertebrate?
a)	Rabbit	b)	Hagfish	c)	Bird	d)	None of these

(b)

Osmoconformers are those organisms whose body is osmotic,  osmotic concentration of internal environment and surrounding sea water are approximately equal. There is no net tendency for water to move in or out of body in osmoconformers. Among vertebrates hagfishes are osmoconformers.