is b.a. from history , eco. ,political science will be faverable for the preperation of i.a.s

you should choose ur subjects based on your interest because allof them are good for IAS. indepth knowledge of any subject can fetch good marks.you can choose subjects outside your grad or PG but if tyey are common than it is better. a few secs ago

Yes it is for sure. However you should NOT be entirely dependent only on the BA Subjects, but outside your curriculum as well.