Which one of the following is a stalked echinoderm?

Crinoids that are attached to the sea bottom by a stalk in their adult form are commonly called sea lilies. They have ten or more arms extending from this central stalk which gives them the appearance of a sea lily. They are sessile and mostly remain attached to a substratum but can change their location for finding food. 

Since Rhizocrinus is a sea lily, it is an example of a stalked echinoderm.