The third box plot is your answer
It's the y intercept.
If y = a then every point on the line would be (x,a)
The lines slope is 0. I know that has nothing to do with the question, but it is true and it gives me 3 things to tell you.
Let's look at the corresponding ratios:

And we see that the three aren't equal.
Hence, $\Delta ABC$ and $\Delta EDC$ are not similar.
Answer:
Geometric
Step-by-step explanation:
Given terms are {3, -1, 1/3, -1/9............}
If we have common difference between the terms then it is arithmetic
If we have common ratio between the terms then it is Geometric
Difference of 3 and -1 is 4
Difference of 1/3 and -1 is -4/3
Common difference it not same so it is not Arithmetic
Now we check common ratio
we divide second term by first term
first term is 3 and second term is -1

now we check with next two terms

common ratio is -1/3
So this is Geometric