Which of the following is an argumentative thesis? A. Building a fence around the border with Mexico is a flawed approach to containing illegal immigration, and will result in devastating effects on the natural environment. B. Construction of a fence around the border with Mexico is a highly controversial approach to stemming the tide of illegal immigration. C. Some believe the best way to contain illegal immigration is through construction of a border fence; however, many others believe it is an ineffective and damaging means of approaching the problem. D. A fence is currently in the process of being constructed around the border with Mexico, to mixed results.