You can take admission into BCA from any background be it commerce, science or arts but to persu bsc you need a strong background of maths. However, BCA is somewhat better than Bsc due to it's high scope. Bsc is concept oriented course will be teach you about basic concepts of CSE whereas in BCA you'll learn about new technologies. Moreover BCA is considered as a technical course hence it's scope is higher.

Hope it helps.

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