Self or tution

its depend on subject which he can eaily understand then he can study self or not then go for coaching classes

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For Audit Self Study one of the best book is Pankaj Garg, it is best book for understanding rather than craming.......in this book after every small topic there are review questions with their answers, those help a lot in prepration.you can use Practice manual for Questions too with this book, if u willl not use then also this book alone is sufficient on its own.........................Best of Luck dude!