The correct answer should be locate basic information.
When you are doing the preliminary research, you are just reading through a bunch of sources and information that you may or may not use while writing. You still aren't deciding which exact sources you are actually going to use, but rather just trying to find them and later on make that decision during another stage of writing.
The answer is the last one. Hannah thinks that cats are happier outdoors than they are indoors.
The statement, Keep to your topic; follow the thesis as it evolves, is true!