Does the graph below represent a function and is it onetoone
     Does the graph below represent a function and is it one-to-one?  It is a function and it is one-to-one.  It is a function but not one-to-one.  It is not a function but it is one-to-one.  It is not a function and it is not one-to-one. 
  
  Solution
The graph represents a function , but it is not one-to one, as except for y = f(x) = -1, , every other y- value has 2 corresponding values of x . Thus y = f(x) is not one-to one. The answer B is correct.
Note:
Such a graph usually represents a modulus function.

