Based on the allusion to tory whips, readers can infer that the speaker thinks that
a. most people do not think about the racial tension in england.
b. oppressive political groups are a thing of the past.
c. there are many examples of oppression throughout history.
d. the racial tension in england is not affected by past events.

The correct answer is C. Based on the allusion to Tory whips, readers can infer that the speaker thinks there are many examples of oppression throughout history since the term is used to refer to the modern conservative British party, known as the Tories.

faulty parallelism is a construction in which two or more parts of a sentence are equivalent in meaning but not grammatically similar in form.

the correct version of this faulty parallelism in the sentence is:

the hikers knew that the hike was six miles, that it usually required the entire day, and it would not be wise to start after 10: 00 a.m.

the problem is the last sentence, the first two have a basic subject+verb+object structure.

so, to give a proper balance to the structure, or better said, to give a parallel structure, we must write a basic s+v+o structure in all three sentences:

the hikers knew that the hike was six miles, that it usually required the entire day, and it would not be wise to start after 10: 00 a.m.