Question

input = 1: exactly one output, which is 2
input = 2: exactly one output, which is 1
input = 3: more than one output
when the input is 4, how many outputs are there?
exactly one output, which is 3
exactly one output, which is 5
more than one output

Explanation:

Step1: Analyze the graph for x=4

Look at the graph, find the column where \( x = 4 \). Check the number of points (outputs) at this \( x \)-value.
From the graph, at \( x = 4 \), there is one point (output) with \( y = 3 \)? Wait, no, wait. Wait, the graph: when x=4, there is one dot? Wait, no, the points: x=1 has y=2; x=2 has y=1; x=3 has y=2 and y=3? Wait, no, the given info: input=3 has more than one output. Then for x=4, looking at the graph, the point at x=4 is y=3? Wait, no, the graph shows at x=4, there is one point? Wait, no, the options: wait, the options are "exactly one output, which is 3", "exactly one output, which is 5", or "more than one output". Wait, looking at the graph, the x-axis: x=4 has a dot at y=3? Wait, no, the grid: x=4, y=3? Wait, the graph's points: x=1 (y=2), x=2 (y=1), x=3 (y=2 and y=3), x=4 (y=3). Wait, no, x=3 has two points (y=2 and y=3), so input=3 has more than one output. Then x=4: how many points? Looking at the graph, at x=4, there is one point (y=3)? Wait, no, the options: the first option is "exactly one output, which is 3". Wait, maybe I misread. Wait, the graph: x=4, y=3 is a point. So when input is 4 (x=4), there is exactly one output, which is 3? Wait, no, wait the options: let's check again. The options are:

1. exactly one output, which is 3

1. exactly one output, which is 5

1. more than one output

Wait, maybe the graph at x=4 has one point (y=3). So the correct option is the first one? Wait, no, wait the graph: looking at the coordinates, x=4, y=3 is a point. So when x=4, there is exactly one output (y=3). Wait, but let's confirm. The input is x, output is y. So for x=4, how many y's? From the graph, at x=4, there is one dot (y=3). So the answer is exactly one output, which is 3.

Answer:

exactly one output, which is 3