Dear aspirant,
If you Future aim is to do research and learn the field with great experienced professors teaching you with great detail then go for ocean at IIT Madras. In this field you will be able to research and truely enjoy the course. Don't expect on campus placement as there are only few companies available. But you can try off campus just that initially there won't be a fat pay.
If you are studying from job perspective then go for I.T field  at IIIT or mining.

Dear Aspirant,
IIT Madras,IIT BHU,IIIT allahabad are best colleges if you have much confusion go for IIT madras.being in IIT is everyone's dream.Ocean engineering branch is also the best branch to opt.yoi can be easily placed. Among IIT BHU and IIT Madras ,IIT Madras is best so you can go for that.
Thankyou
Hope it helps

mining at iit bhu is good .
It at iiit Allahabad is also good.
If you want iit tag go for iit bhu.

IIT BHU

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IIT Madras (IITM)

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IIIT Allahabad

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