Though you have mentioned the areas having your knowledge in Coding, Software Developments and Products Design but having knowledge in these domains are not enough for the sustenance of your MS Course. You should examine the subjects with which you have graduated and choice of the subjects should be followed accordingly.
With the changing of time, we see that no branch as indicated by you is less important. While talking about Coding, a sound knowledge in this field make you far efficient than others because of your sound grasping analysis apart from your core skills in coding and lot of demands are foreseen in the future as well with the enhanced creations of jobs and hence this area might be pursued for your masters courses.
Software Development- The task of the software developer stretches from making or augmenting software applications for the mobile services such as cell phones, tablets etc.
The most exciting programming languages are Java, Java Script and Python and hence updating in this area such as Software Skills, Designing, Testing and Building to meet the end user's need would certainly multiply their career prospects in their job services.
Product Design- This would cover multiple range of designing such as Graphic Design, Product Road Design, Crafting, Design Testing etc and hence this could be the fascinating area apart from your substantial growth if you have the real appetite for the same.
What I suggest you you need to choose your specialisation area in MS being undertaken in USA with your own interest provided you have had such a skill set your graduation stage. Of all the three, they have enough potentials for the tremendous growth.