Hello

Compared to the other two MSc in Information Technology is a rather new branch. After MSc in IT you can become a Software Engineer.,Computer Programmer.,Interface Engineer.,Java Developer.,Project Manager,IT Consultant and Network Administrator.

Msc in Computer science is a good stream since after NEP it is expected that computer science will be taught in every school and coding will be compulsory since class 6 which will provide huge opportunities for a graduate from computer science in the education sector. You can also develop apps and make website (website edeveloper) if you gain skills in the course which even as a free lacer can provide you great jobs.

Msc mathematics is a rather known and old subject. It is well reputed and you can get huge opportunities in the education sector if you choose this.

Overall, I will suggest you to go with MSc Computer Science if you are really interested in Programming and developing. If you like maths more and are passionate to get in the education field then go for maths.