Respuesta :
For an essay such as this one to be powerful, it needs data to support it. The author can take a stance, but it must be supported by data, and that is the purpose of the fourth section; it cites generalized sources to provide evidence that people with disabilities are generally considered inferior. Overall, this helps contribute to the main point because it illustrates the problem that the passage is attempting to explain.
Explanation:
1.The authors include part 4 in this section because part 4 contains the data to support the rest of the section.
2.Part 4 is related to this because it contributes to the main claim. The section would not be very powerful if it was not cited.