The assertion (A) is correct as footloose industries can be located in a variety of places, such as areas where transportation and infrastructure are flexible, and where access to markets or raw materials is not a significant constraint.
The reason (R) is also true because the location of footloose industries is indeed influenced by transport network accessibility. A good transport network allows such industries to be located in different areas since they are not tied to raw material sources.
Therefore, (R) correctly explains (A).