In Retail to get depth and breadth of the brand is Merger & acquisition the best Way (it will be kind if you can detail your answer) ? yes/ No

Merger& Acquisition is a good solution but not always the best.It can give you what you want if you planned it well and made the right selection of who to merge with or who to acquire, but if you started it wrong it will not only fail to give you what you want but also may destroy everything.  

The answer is yes and no. Brand merger or acquisition should not happen for the sake of it i.e for financial gain only. But both the brands strength and USP can be exploited on a broader canvas to gain a long term benefit.  The shortcoming can be overcomed and a new robust product portfolio can come out of the merger.