The eligibility for the CAT examination is that the candidate need to complete the Graduation degree in any stream with at least 50% marks from a recognized university. As a result, if you wish to go for the CAT examination, then you have to complete the course of 4 year i.e., on the final year of BSc in Agirculture you can apply for the CAT examination, as the final year appearing candidates are also eligible for the CAT examination.

For more information regarding CAT examination consider the link provided below:

https://bschool.careers360.com/articles/cat-eligibility-criteria#:~:text=Question%3A%20Who%20are%20eligible%20for,PwD)%20are%20eligible%20to%20apply.

I hope this helps. Wish you a great day!