The quantity demanded changes slightly with the price.
This is a demand curve, not a supply curve, so we can immediately knock off the first two options that deal with production (supply).
Now with the last two answers we just have to decide if the change in demand is slight or great. Look at the two data points that have dotted lines leading to them.
p1= Price $50, demand 15
p2= Price $30, demand 20
The price dropped $20 but demand only rose by 5 units, so this is a pretty slight change. The up/down tilt of the curve will tell you if the change is big or small.
