To figure out if something is increasing or decreasing, you must read the graph from left to right. If it appears to be going down, then it is decreasing. When it appears to be to be going up, it is increasing. For both A & B, the graph is decreasing. When you look from when the x-values are between 2.5 and 3.5, you can see the line going down. That means it is decreasing.
