Hello Rahul,
I would like to mention the eligibility criteria of IISER 2019 varies according to the different channel of admission. It must be noted that fulfilling the eligibility criteria before applying is mandatory.
Below is the info from careers360's site.
For KVPY: Candidates are required to have a KVPY fellowship commencing from the academic session 2019-2020.
For JEE Advanced: Candidates of general category must have secured a rank in JEE Advanced within the limit which will be prescribed by the official authorities.
For SCB: The concerned authorities will determine the minimum cut off that a candidate is required to meet for IISER admissions 2019. It is mandatory for the candidate applying through this channel to appear in IISER aptitude test 2019.
I would suggest you visit the careers360's link given below which has detailed info of the aptitude test.
The link for the same is:https://engineering.careers360.com/exams/iiser-aptitude-test
Hope this helps and all the very best to you!
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