Which of the following phyla exhibit bilateral symmetry?

$S$ Statement: Aquatic life,gills,fins,and scales are characteristics of the fish group.
$R$ Reason: External ear (pinna) and hair on the body are characteristics of the mammalian group.
$(a)$ Both $S$ and $R$ are true,$R$ is the correct explanation of $S$.
$(b)$ Both $S$ and $R$ are true,but $R$ is not the correct explanation of $S$.
$(c)$ $S$ is true and $R$ is false.
$(d)$ $S$ is false and $R$ is true.
$(e)$ Both $S$ and $R$ are false.

All of the following are monoecious,except

Which of the following are cold-blooded (poikilothermic) animals?

Which of the following are correctly matched with respect to their taxonomic classification?

Column $-I$ represents the animal class, while Column $-II$ represents the exoskeleton. Choose the correct option:

Column $-I$	Column $-II$
$(A)$ Cartilaginous fishes	$(i)$ Cycloid scales
$(B)$ Bony fishes	$(ii)$ Epidermal scales
$(C)$ Reptiles	$(iii)$ Placoid scales