The adult stage of a housefly or mosquito is known as:

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.

Read the following statements and find out the correct statement.
$a$. Urinary bladder is absent in fishes
$b$. Gambusia fish eradicates mosquito larva
$c$. Ampulla of Lorenzini present in dogfish act as thermoreceptors
$d$. Electric organs are modified muscles

Match the following:

Column-$I$	Column-$II$
$(a)$ Trygon	$(i)$ Echinodermata
$(b)$ Ascidia	(ii) Viviparous
$(c)$ Asterias	(iii) Chondrichthyes
$(d)$ Kangaroo	(iv) Oviparous
$(e)$ Penguin	$(v)$ Urochordata

Which of the following organisms possess a four-chambered heart?

Which of the following represents a correct match of a somatic feature and the animal possessing it?