Answer:
Option C is correct.
Step-by-step explanation:
We have been given the graph
The graph is not of exponential function
Therefore, option A and B are discarded.
Now, We can see the graph is starting from 37
And the difference between Amount of water from the table is 19-22 that is -3
So, the graph is arithmetic
So, applying the formula ; d is common difference here we have d= -3
Therefore, option C is correct.