I'm doing B.Sc. Mathematics. Final year. Next MCA or MBA what will choose is best.

Well, it's your choice as both the courses are good and serves same salary package. MCA is all about the development and designing and MBA is all about the management skills you have to choose that where is your interest in my opinion both stand in equal row.

Hello, Choose MBA if you want to make a career in the business domain. Choose MCA, if you want to make a career in the technical/technological domain. Choose the one which you genuinely feel more interesting and aligned with your career goals.