Use the vertical line test to determine whether the graph re
     Use the vertical line test to determine whether the graph represents a function.  Yes, the graph is a function.  No, the graph is not a function. 
  
  Solution
If a vertical line can be drawn anywhere on a graph so that it hits the graph in more than one spot, then the graph is NOT a function.This is called vertical line test.
In the graph if a vertical line is drawn at anywhere on graph,then it touches the straight line in that graph only once.So,it is a function.
The option \'a\' is correct one.

