​A researcher working on island biogeography mapped how isolation-controlled immigration (I), and area-controlled extinction (E), will act on number of species present on the islands. He forgot to label the size of the islands (small or large) and the location of the islands (near or far) on the graph.​

​Using information from MacArthur and Wilson’s equilibrium theory, select the option that correctly identifies A, B, C and D in the figure above.​

Correct option is C

Explanation-

Given:
     2 Immigration curves: A and B
     2 Extinction curves: C and D
X-axis: Number of species present
Y-axis: Rate (either immigration or extinction)

Immigration Curves (A & B)
Immigration is higher when islands are near the mainland.
               Curve A starts higher, so it must represent a near island.
               Curve B is lower → represents a far island.
So, 
                A = Near
                B = Far
Extinction Curves (C & D)
Extinction is lower on larger islands because of more resources, space, and stability.
               Curve C lies lower → represents large island (lower extinction).
               Curve D is higher → represents small island (higher extinction).
So, 
                C = Large
                D = Small

Correct Answer: Option c
                 A Near (higher immigration)
                 B Far (lower immigration)
                 C Small (higher extinction)
                 D Large (lower extinction)