Answer:
The correct option is 4.
Step-by-step explanation:
From the given graph it is clear that the line passes through the points (1,15) and (2,30).
If a line passes through two points then the slope of the line is

The line passes through the points (1,15) and (2,30). So, slope of the line is



Slope of the line is 15. Therefore the correct option is 4.