Answer: Choice C
Step-by-step explanation:
As the person spends more time raking, the number of leaves will go down. Therefore, we have a negative correlation. Such correlations occur when one variable goes up while the other goes down (and vice versa).
The reason why it's considered negative correlation is because the regression line has a negative slope.
This is why choice C is the answer. This assumes that no extra leaves fall on the ground, and we assume that we don't have nearby leaves blow into the yard.
In contrast, something like choice A has both variables go up together. As the temperature rises, so does the ice cream sales. The same goes for choice B. We consider these cases to have positive correlation. Choice D doesn't appear to have any correlation at all. The person's height doesn't have any connection to the number of pets they may have.