To find the ratio that represents the constant of proportionality between the amount of raspberry scoops and the cups of lemonade, we should consider the given relationship: 2 scoops of raspberry for every 5 cups of lemonade.
This relationship can be expressed as a ratio:
\[ \text{Raspberry scoops} : \text{Lemonade cups} = 2 : 5 \]
To find the constant of proportionality, we can also express it as a unit rate:
\[ \frac{\text{Raspberry scoops}}{\text{Lemonade cups}} = \frac{2}{5} = 0.4 \]
Now let's analyze the options:
- A. (2, 5) corresponds to the original ratio \(2 : 5\).
- B. (5, 2) is the inverse and does not represent the proportionality.
- C. (1, 2.5) does not match as well.
- D. (2.5, 1) does not match either.
The original ratio \(2 : 5\) gives us the understanding of the relationship, but for determining the constant of proportionality, we are more interested in the unit form.
Thus, the constant of proportionality is represented by:
\[ \frac{2}{5} \Rightarrow \text{which can be represented as} (1, 2.5) \]
as multiplying both sides of \( (2, 5) \) by \( \frac{1}{2} \) gives us \( (1, 2.5) \).
So the correct answer, which represents the unit ratio or the constant of proportionality, is:
C. (1, 2.5)