Identify which graphs are functions and which graphs are not.

Step-by-step explanation:

We will apply the vertical line test in the given graphs to test them for a function.

Option (1) [First in top row]

If we draw a vertical line from any point, none other point of the graph passes through it.

Therefore, Graph (1) is a function.

Option (2) [2nd in the top row]

When we draw a vertical line through (2, 1), another point (2, -1) will pass through this line.

Therefore, Graph (2) is not a function.

Option (3) [1st in the second row]

In this option when a vertical line is drawn from (2, 1) two more points (2, 2) and (2, 3) pass through this line.

Therefore, graph (4) is not a function.

Option (4). [2nd in the 2nd row]

In this graph only one point lie on the vertical lines drawn.

Therefore, Graph (4) is a function.

the correct answer is 5