Answer:
C
Explanation:
The scale factor of rectangle HIJK to rectangle LMNO is:
"What" multiplied by the area of rectangle HIJK will give us the area of rectangle LMNO?
This "What" is the scale factor. (For area, we will put k^2 in place of "what" and solve for k to get the scale factor. Let's do this:

Correct answer is C.