Answer:
C. 1 and 3
Step-by-step explanation:
You are right, now here's why.
You are looking for two equations that have the same constant of proportionality. That means they behave the same, that if you enter a X value in one, you'll get the same effect as if you enter it in another.
If you look at all four equations, you'll see that 1 and 3 are essentially the same thing, just that the first one is simplified (4y = 3x) while the other isn't (8y = 6x). But for each time you enter a X value, the Y value will be 33% (1/3) bigger.
