Highlights Ministry of Home Affairs has released mock tests for Intelligence Bureau's Assistant Central Intelligence Officer Tier-I 2021 exam. The IB ACIO Tier-I 2021 Exam is scheduled to commence from February 18. The exam will be conducted in 3 shifts each day at various centers across the nation. The Ministry of Home (MHA) has released a number of mock tests for the upcoming recruitment exam for the Intelligence Bureau’ Assistant Central Intelligence Officers (IB ACIO). This year IB ACIO exam will be held for filling 2,000 vacancies in the Intelligence Bureau. Here is the link to IB ACIO mock test- IB ACIO Mock Test The qualifying mark for the exam is 35 marks for unreserved category, 34 for the candidates belonging to OBC and EWS category and 33 for SC and ST categories.