algorithm - new graph with adding 1 edges and number -

In the preparation class for

ACM-Contest , our teacher has given us a printed page solution The problem is written on one page, that the following facts are true of 2 , but they will not say, why or what :

"With the addition of new 1 edges in the guided graph, how many of these can be true about the number of components associated with this article?

  +) Max 1 In the unit +++) Probably not changed. ++++) It may be that there is a shortage of more than 2 units.  

Anyone can clearly see it with our teams ?

(+) is a lie (under "liberal interpretation" ", That is, that means there is no defect) and (++) is false and (++++) is true because if we add a feedback arch from one end of the path to another, then make it a cycle Are there And we have strong components 1. (+++) is clearly true.

  Before (4 strong components): * - & gt; * - & gt; * - & gt; * 1 strong component after version A): ___________________ | | Wei | * - & gt; * - & gt; * - & gt; * After version B (4 strong components): ___________________ | | | V * - & gt; * - & gt; * - & gt; *