Select the correct option from the following.

Given below are two statements.
Statement $I$: $Rauwolfia$ $vomitoria$ found in Himalayan ranges shows variation in potency and concentration of active component reserpine.
Statement $II$: Ecosystem diversity is observed in regions of Rann of Kutch.
In the light of the above statements,choose the correct option.

Read the following statements:
$I.$ Species diversity increases as we move away from the equator towards the poles.
$II.$ Stellar's sea cow and passenger pigeon got extinct due to overexploitation by man.
$III.$ Lantana and Eichhornia are invasive weed in India.
$IV.$ The historic convention on biological diversity was held in $1992.$
Choose the option containing correct statements.

Which of the following pairs of an animal and a plant represents endangered organisms in India?

What is true for $X$ in the figure representing the species-area relationship?

If the Bengal tiger becomes extinct,then . . . . . . .