MBA is a course which offers to develop ones business perspective. Hence there is an increasing demand for the course.
In order to select a specialization you will have to check what you are interested in. For e.g. Finance is the most seeked after stream in MBA, but if you are not a finance-person,do not want to get into calculation and analysis and understanding of the financial market bit then how can you excel in ti,in spite of it being one of the 'hot' careers.
Hence you will have to talk to your professors and the various professionals into the field to get the first-hand information about the streams and career opportunities in them.
Hope this helps.