C=chalaak
B=Badmash
I=insaan

:-D I know only this

ANY GRADUATION, IN CBI IT IS TAKEN BY SEEING MANY THINGS LIKE FAMILY BACKGROUND, YOUR BACK GROUND, YOUR COLLEGE AND SCHOOL HISTORY ETC. SENIOR OFFICER'S REFERENCES ALSO CONSIDERED , REFERENCE BEING THE ABOVE MENTIONED QUALITIES.

Recruitment to the CBI is directly through competitive exams, or through deputation from the police service or promotion from within the service. While most of the senior posts in the CBI are filled by IPS officers on deputation, or from other police and all-India services, direct recruitment is conducted according to vacancies for junior level posts of Sub-inspector, and for Assistant Public Prosecutor and Senior Public Prosecutor.