as we can see in the graph 1
at x = 3 , y = 1
at x = 6 , y = 2
a x = 9 , y = 3
the common ratio is 3/1 = 3
6/2 = 3
9/3 = 3
so, it has same common ratio, thus it is proportional
in graph 2
at x = 1 , y = 4
at x = 3 , y = 6
at x = 5 , y = 8
the common ratio is,
4/1 = 4
6/3 = 2
so, it is not proportional.
thus, the answer is option B