Which of the following statements is incorrect?

Find the mismatched pair regarding the exoskeleton.

Give an example of the following:
$(a)$ $A$ viviparous animal
$(b)$ $A$ fish possessing a poison sting
$(c)$ $A$ fish possessing an electric organ
$(d)$ An organ which regulates buoyancy
$(e)$ An animal which exhibits alternation of generation
$(f)$ An oviparous animal with mammary glands

Select the animals having an open type of circulatory system:
$(i)$ $Ascidia$
$(ii)$ $Cockroach$
$(iii)$ $Earthworm$
$(iv)$ $Prawn$
$(v)$ $Silver$ $fish$
$(vi)$ $Snail$
$(vii)$ $Squid$

Column $-II$ below consists of brief descriptions of organisms in column $-I$. Which of the following is an incorrect match between column $-I$ and column $-II$?

Column $-I$	Column $-II$
$A$. Millipede	Terrestrial organism with two pairs of jointed appendages attached to each of its many body segments and respires through trachea.
$B$. Nereis	Numerous setae on lateral appendages called parapodia.
$C$. Taenia solium	Body is covered with cuticle,alimentary canal absent.
$D$. Ctenophores	Radially symmetrical,devoid of cnidoblasts,polyp stage present in their life cycle.

Which one of the following is not a nematode parasite?