Hi Anu.
So a person is asking for a bribe to increase your CBSE marks and you're in dilemma whether to trust him or not. Well, all I can say is honesty is always the best policy and even if you trust him and he manages to increase your marks by some percentage, how long will it work. Ultimately it's you who have to carve a niche for yourself to have a successful career. Hence, believe in yourself, accept what comes and stay determined with your ambitions.
Nobody can know what the intentions of a person are. There have been many cases where such people have managed to fool innocent students and ran away with money. Also CBSE is an extremely tough exam to do anything as such.
Nothing gives more satisfaction than rewards (in this case, marks) you obtain of hard work and honesty. Be truthful to yourself and your perseverance.
All the best.

no never , certainly that person is a fraud.

Hi Anu
Don't trust on that type of person .
These are the fake person who wants to take money from you only nothing else. They can't increase your  marks in any case . If your score low then why you take tension you have a chance to appear again for improvement . So don't trust on that person .
Be careful
Best of luck
Thanks