Match the category in Column-$I$ with their description in Column-$II$.

Column-$I$	Column-$II$
$i$. Extinct	$a$. Decline in species population from $50\%$ to $70\%$ over last $10$ years.
$ii$. Endangered	$b$. Species that are abundant.
$iii$. Vulnerable	$c$. Species of which its last individual has died.
$iv$. Least concern	$d$. Decline in species population from $30\%$ to $50\%$ over last $10$ years.

The given pie chart represents the biodiversity of invertebrates. Identify $a, b, c,$ and $d$.

What does '$W$' represent in the given figure?

Using the provided graph,determine the percentage of bird species that will be lost if the island's inhabitable land area is reduced from $100,000\, km^2$ to $1\, km^2$.

Which of the following statement$(s)$ is/are correct?
$(i)$ Rich biodiversity is not essential for ecosystem health.
$(ii)$ The current rate of species extinction is $100$ to $1000$ times faster than the pre-human extinction rate.
$(iii)$ Steller's sea cow became extinct due to overexploitation by humans.
$(iv)$ Even if we combine all biodiversity hotspots,they cover less than $2 \%$ of the Earth's land area.
$(v)$ The rate of mass extinction can be completely reduced by strict protection of hotspots.

The World Summit on Sustainable Development held in $2002$ in Johannesburg,South Africa,pledged for: