Take a look at line 27: "Competing for votes, parties seek to offer different sections of the electorate what they most want' they do not ask what the majority thinks of an issue, but what policy commitments will sway the electoral decisions of particular groups."
The strategy of political parties in a polyarchy referenced in this section is clearly expressed by answer choice B.
D sounds reasonable, which leads me to guess that you made an inference based on the information in the passage. However, with this type of question, we must pay attention to what is specifically written in the passage. You should be able to return to the passage and find direct support for the correct answer, which I was unable to do for D.
