This question haunts me! I don't know which one to choose. Please help me by giving me advice about the courses!

 

I don't see how others can answer a question that should be based on personal leaning and preference?
Max.

 

Think about which interests you more. In which area would you prefer to spend nearly a third of your waking hours during your working career?

 

The first thing to do is determine what the main differences are between the two areas. Have you done that already?

If you still don't have a good feel for the differences, then go talk to your advisor (or if you don't have one, to one of the academic advisers at the institution) and explore that further until you do have a decent feel for the differences.

Then it's a matter of deciding which is a better fit for YOU -- that's something that no one else can really help you with. You might look at the course descriptions for those courses that are difference between the two areas and ask yourself which ones, as a whole, sound more interesting to you.