How do I choose research project topics for the project requirements in graduate classes?
Much of your approach will depend on the requirements for this specific project, but there are some generic guidelines that one should follow when beginning a new research project.


You should choose something interesting to you. This seems obvious, but some people fall into the trap of choosing what seems easier or less work and end up losing motivation because they do not enjoy what they are researching. If your instructor gave you 5 areas of applicability to choose from, the first thing to do is find what interests you most. I would strongly caution you against picking something that seems like the quickest option just because you have a time limit.
Become familiar with the area. If all of this material is new to you, do some cursory research wherever you can find it (all the way from a reputable book to Wikipedia). You do not need to become an expert for this class project (since it’s not your thesis), but you need to have a working knowledge and basic familiarity with the topics. 
Read/write a literature review. A literature review will tell you what work has been done in a research area. You should read literature reviews that have already been written, but a good researcher will write their own too (even if it is just a smaller section in the paper). By assessing the work being done in your specific area, you will be able to narrow your topic and find gaps in the current research where you can add your own. This is one of the most critical steps to conducting new research. Note: This part of your research should focus on peer-reviewed material (like books and journal articles), not the aforementioned cursory material. 
Narrow your topic as much as possible. If it seems daunting to become an “expert” in your area, you are probably thinking too broadly. Your instructor is not expecting earth-shattering research, so do not worry about your contribution being small.


If you follow these guidelines, you should naturally be able to find a problem to work with that is within your skill level, is interesting to you, and meets the requirements for the course. It is difficult to assess how many hours of work this would take, but if the instructor has not indicated this otherwise, I would use the time as a guideline for how detailed your project should be.