A Marine Biologist Is Asked to Identify an Echinoderm and Is

Multiple Choice

A marine biologist is asked to identify an echinoderm and is given a living sample of larvae to use to achieve this goal. Can the scientist identify the class of echinoderm from this sample, and if so what would be the simplest process the scientist could use?

A) No, the echinoderm cannot be identified.
B) Yes, by observing the positions of pharyngeal slits.
C) Yes, the echinoderm can be identified from the larvae by identifying unique molecular markers for each different class and then analysing the DNA of the sample against them.
D) Yes, the echinoderm can be identified from the larvae by performing a micro-dissection performed by an experienced scientist that is intimately familiar with echinoderms.
E) Yes, the echinoderm can be identified from the larvae by simply allowing it to develop projecting arms and observing their arrangement which will be diagnostic of the class.