Answer:
Option a. Logistic
Explanation:
We will analyze every option one by one
a. Logistic graph
Logistic graph is a typical S-shaped graph showing three curves.
Starting curve shows a less growth because less number of species.
Then a steep curve showing fast growth because of good number of species then curve showing less growth because of limited resources in the environment.
This option is the correct option.
b. Exponential graph
Exponential graph shows a steep growth in its curve so this option doesn't match the graph.
c. Linear graph
Linear graph shows a straight line so this option is not correct.
d. Triangular
Triangular graph is a three dimensional graph having three vertices. So this option is again not correct.
Therefore Option a. Logistic graph is the correct one.