Answer:
Option D ---> y=5x
Explanation:
When a line is directly proportional it means it crosses the origin so has a y- and x-intercept of 0.
So if we use the format y=mx+c, it will work but our c value will be 0 as I explained above .
To work out the gradient we simply take 2 points (0,0) and (1,5)) on the graph and use the gradient formula :
m = change in y ÷ change in x
m = 5÷1
m = 5
Therefore our direct proportion equation will be y=5x
Hope this helped and have a good day