There are different things that geographers would like to know more about. They generally want to know why there are various places on earth that are similar to each other. In order to help them with their research, they use some tools. The answer to this question is A.
These tools are needed so that everything will be categorized in an easier manner. You can learn what your geographic location is based on the tools that can be used. Just imagine how useful this is going to be for you. Sometimes, the characteristics of the place are also used in order to determine the current location.