The graph represents a linear function. (I need this right now no joking please)

[tex]y=mx+b[/tex] is general equation of linear function
We see that graph is decreasing ⇒ m<0
We have dirt (0;-3) ⇒ b=-3
Then let's try find m
look on dirt (-5;0), x=-5, y=0 ⇒
[tex]0=-5m-3\\-5m=3\\\\m=-\dfrac{3}{5}[/tex]
The answer is D