The Y axis is up and down and the x axis is side to side. So first we want to look to see which line crosses the y axis the the up and down black line.
When you are finding a coordinate you set it up like this (x, y). You will find x first and y second.
So we are down to two graphs graph a and graph c. Know both of them cross at the (0,-7) mark but it asks for one other thing a well.
On a graph when something decreases it will go down and when something increases it will go up. So that tells me it is graph C.