Which option is better in terms of salary prospects: engineering from IIT or merchant navy?

Surely merchant navy is the best options now 1. You are just 17 or 18 years young and started living a disciplined and a professional life. Life in Maritime institutes are semi-military. 2. You are getting a stipend of $500 to $700 per month in your cadetship (generally a cadet is 18 years young ).

Merchant Navy at officer level has better starting salaries in comparison to engineering from top IITs. But in long run IITian will have better salary and career prospects. Also before choosing career evaluate sea life challenges also.