Select the correct option for $X$ and $Y$ in the chart shown below.
[Chart Structure: Primitive Reptiles -> (Sauropsids,$X$); $X$ -> $Y$; $Y$ -> Therapsids]

Choose the correct statement from the following:
$A$. Charles Darwin travelled around the world in a ship called $HMS$ Beagle
$B$. There has been gradual evolution of life forms
$C$. According to Darwin,fitness refers to physical fitness only
$D$. Fossils are remains of hard parts of life forms found in rocks
$E$. Hugo De Vries,a naturalist worked in Malay Archipelago.

List $10$ modern-day animals and,using internet resources,link them to a corresponding ancient fossil. Name both.

Which two geographical regions are separated by high mountains?

Define and explain divergent evolution,convergent evolution,and mutation.

What is common between a moth,a frog,and a mosquito?