Ca and b.com simultaneously

Both have their own advantages and disadvantages.

A Bcom graduate can fully concentrate on CA as one course is already completed

Whereas in case of non graduate, age factor matters. One can become a CA at an early age than after completing CA

Although BCom student can directly join articleship, whereas non graduate only after clearing 1st group can join articleship.

So ultimately it depends upon a student how he/ she can handle the priorities. Because it is all about priority of article ship, studies, classes etc

The best is b.com (a&f)offered by ignou university specially for ca students. In order to get the degree, you must have cleared ipcc both groups and also appear for 6 papers of ignou course. It's got the same validity and recognition like other universities. Details are available in icai site as well as ignou website.