I am not a CA myself, but know plenty of CAs in the family to tell you that you dont need a masters nor do you need an MBA for a CA qualification in India. I do know that now it is even possible to go through the CA process without even a bachelor's degree; you need to sit through an articleship process.
The best place to seek information would be the CA institute, particularly regarding anything special about being an NRI applicant.
1) Algebra-101 2) Sequences 3) Set combinatorics 4) 3-D geometry
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