The reasons behind conserving biodiversity can be grouped into categories,which includes?
$I$. Broadly utilitarian
$II$. Narrowly utilitarian
$III$. No utilitarian
$IV$. Ethical utilitarian
Choose the correct option.

What is the full form of $IUCN$?

Initially $A$ biodiversity hot spots were identified but subsequently nine more have been added to the list,bringing the total number of biodiversity hot spots in the world to $B$. These hot spots are the regions of accelerated habitat loss. Three of these hot spots—Western Ghats and Sri Lanka,Indo-Burma,and Himalaya—cover our country's exceptionally high biodiversity regions. Although all the biodiversity hot spots put together cover less than $C$ $\%$ of the earth's land area,the number of species they collectively harbour is extremely high,and the strict protection of these hot spots could reduce the ongoing mass extinctions by almost $D$ $\%$. $A, B, C$ and $D$ in the paragraph refer to:

What percentage of the total oxygen in the Earth's atmosphere is produced by the Amazon rainforest (in $\%$)?

What is the difference between endemic and exotic species?

Define/Explain: $\gamma$-diversity.