we will proceed to graph each case to determine the solution of the problem
case a)

Using a graph tool
see the attached figure N

The case a) is not the function in the graph
case b)

Using a graph tool
see the attached figure N

The case b) is not the function in the graph
case c)

Using a graph tool
see the attached figure N

The case c) is the function in the graph
case d)

Using a graph tool
see the attached figure N

The case d) is not the function in the graph
therefore
the answer is
the function in the graph is the option C
