From the graph above, we need to take a reasonable value for the value for point B. As we can see, B is at the left of zero. Therefore, it must be a negative number. As we can see, there are two possible values: -0.8 and -2.25.
If we see the graph, and we compare the distances from 0, point C is 3 units at the right of zero, if we take the number the number -2.25, the number B must be quite far from zero.
Therefore, the most reasonable number, in this case, is -0.8 (option C).