The answer would be: A. y=32x
In a proportional relationship, the graph should pass the 0,0 coordinate. It means if you put x=0 to the equation, the result would be y=0. The graph will go in format of y=mx
In the option B and D, the graph function format is y=mx+b so it wouldn't be proportional.
If you put x=0 in the y=2/x you will not get result since you can't count 2/0
