Which one feature is common to leech,cockroach and scorpion?

What will you look for to identify the sex of the following?

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.

Match the following columns:

Column-$I$	Column-$II$
$(a)$ Gill slits open	$(i)$ Lamprey
$(b)$ Absence of paired fins	$(ii)$ Scorpion
$(c)$ Calcareous shell	$(iii)$ Wuchereria
$(d)$ Absence of flame cells	$(iv)$ Oyster
$(e)$ Ecdysis	$(v)$ Shark

Choose the correct option for the following statements:
$(i)$ Birds are oviparous / viviparous animals showing internal fertilization.
$(ii)$ In cartilaginous fishes,gill slits are without operculum / with operculum.

Which one of the following statements about certain given animals is correct?