If you have interest and talent in two very varying areas, it can be quite confusing which one to pick up as a career. Similarly, if parents think one career would be ideal, while the child is very strongly in favour of another, there will be confusion of choice. Not any more. With globalisation and the widening of the working world, there are ample opportunities to combine two apparently widely differing fields and make a successful career out of it.

Some of the combinations that one can think of are:

Biotechnology + management = Managing biotechnology industries   
Teaching + marketing = marketing faculty, research   
Computers + Design = multimedia, animation, web-page design   
Biology + IT & Computers = Bio-informatics   
Computers + literature/writing = IT documentation    
Medicine + management = hospital administration   
Law + management = Management of legal issues   
Engineering + Mass communication = Publishing, documentation, electronic media, etc. 

The above is only a representative list, to make you think how two very diverse fields can be successfully combined.  Many have gone into more creative and unusual combinations, and made a success of it.

The important factor is to decide which course to study first as a foundation, and then take up the complimenting one.  Many of the upcoming fields do not have well-established and recognised courses at the degree level. So you may choose to lay a strong foundation through a professional course like engineering, medicine, law, agricultural sciences, etc., and then take up the complementary field either as a Masters' course, or even a part-time private programme. With a good professional degree, one can ensure an entry level job. A few months of experience can give you the "feel" of that field, and strengthen your confidence, particularly if you are going to take up a non-conventional career.

Do ensure that you are selecting based on your interest and your ability to succeed in the field, and not because there seems to be a sudden spurt in demand for that career. Demand for any career can go up and down many times in the decades that you are likely to be in professional life.