If your goal is to become an IAS officer, choose a degree that supports UPSC preparation and also provides a good backup:

BA in Political Science, History, Geography, or Economics is ideal for IAS.
BSc or BCom is fine too, but you'll need to study humanities separately for UPSC.
For backup, pick a subject with good job prospects like BBA or Computer Science.

KCET is required only if you're planning professional courses like Engineering or Agriculture. It's not needed for BA or general degrees.

After 10th for IAS