Hello aspirant,

If you belong to the general category then you can give NEET examination any number of times till the age of 25. And for SC/ST/OBC category you can give NEET examination any number of times till 30 years. So it's upon you. You marks are improving every year and also you have a backup as you have taken admission in B.Sc. So you may give fourth attempt. If you can score good like 550+ then you will get good government college. So It's upon you. 

Thank you. Hope it helps!

Hello aspirant!

It's really great to see that you were able to score better each year but it's already been three years so it won't be advisable to drop for the fourth time until you're sure that this time you'll be able to get above 500. Even if you reach here, you'll be eligible for BDS only. I hope this information was helpful!

I wish you all the very best!