Answer:
A. Kelley uses 2 parts blue for every 3 parts yellow.
Explanation:
Given equation that shows the amount of blue food coloring,
![b=(2)/(3)y](https://img.qammunity.org/2020/formulas/mathematics/high-school/jnrius9e0uix1z5h83chel9x705a30uduu.png)
Where,
y = amount of yellow food coloring,
If y = 2,
![b=(2)/(3)* 2=(4)/(3)](https://img.qammunity.org/2020/formulas/mathematics/high-school/zhxotvm52igfm1hdh6pypy42kn68o6kaq1.png)
i.e.
parts of blue for every 2 parts yellow.
If y = 3,
![b=(2)/(3)* 3=2](https://img.qammunity.org/2020/formulas/mathematics/high-school/lnw74sidnuzwt98hxvxowl6pldmpv116qb.png)
i.e. 2 parts of blue for every 3 parts yellow.
If y = 5,
![b=(2)/(3)* 5=(10)/(3)](https://img.qammunity.org/2020/formulas/mathematics/high-school/hx3k7r5k11b3iudzn9ruzkwkfsn1n23auf.png)
i.e.
parts of blue for every 5 parts yellow.
Hence, OPTION A is correct.