IIT guwahati Mnc will be a great choice as IiT guwahati is a developed IIT, and Mnc is only available in some IITies only so will be a great and demanding choice. If cse is your interest then you can go for IIT Indore , IIT Indore have a good placement in cse

I would have chosen IIT Guwahati. If you decide a college with just placement then you are ignoring much better factors. Rich campus culture and good exposure to seniors really matters. And MnC is one of the best department of IIT Guwahati and the degree is BTech not Bsc unlike other iits. 

If you are interested in CSE I would suggest IIT Indore CSE. Though IIT Guwahati is older and more reputed, recently IIT Indore has shown a lot of improvement in the CSE department. They have a very good coding culture and recently they have produced great coders.
However I would suggest you to go through the course materials in each of the branches from the respective IIT sites. See if you like one better. Also try contacting seniors from each college and know about the life there

IIT Indore

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IIT Guwahati (IITG)

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