As per the rule,we get the bonus of 100 points at the score of 200 points. And i have not received these points yet. Can anybody help me in answering this question and provide me a valid reason for not receiving the points yet?
As per the Help section:
If you are an experienced Stack Exchange network user with 200 or more reputation on at least one site, you will receive a starting +100 reputation bonus to get you past basic new user restrictions. This will happen automatically on all current Stack Exchange sites where you have an account, and on any other Stack Exchange sites at the time you log in.
Basically, you only get the +100 bonus points if you have 200+ points on ANOTHER StackExchange network site.
According to your profile, you are only active on Drupal Answers, so you don't qualify for the "bonus" points.
You got the bonus reputation right 13 minutes ago.
Getting the bonus reputation is not immediate; as far as I know, it requires a cron task to run for you to get it.
It requires you to have accounts on more than one Stack Exchange, and the accounts must be associated, which means they share the same OpenID account for the login.
The 'association bonus' is only applicable if you have another account on the network that already has 200 points.
As far as I can see this is your only account on the network, so you're not eligible to receive the bonus.
However, as you have reached 200 points on this site, if you now join another site in the network you'll receive the 100 points bonus.
Please see How does reputation work? (at the bottom) for more information.