Read the excerpt from anthem. perhaps, in those days, there were a few among men, a few of clear sight and clean soul, who refused to surrender that word. what agony must have been theirs before that which they saw coming and could not stop! which best describes how the words “clear sight and clean soul” reflect the philosophy of objectivism?

Objectivism is a philosophy that stresses the external rather than the internal. They believe that most things exist outside of what people know or feel and that the truth especially exists beyond what people know. 
The phrase "clear sight and clean soul" supports this belief because in order to see things that are outside of yourself you need to have clear sight, the ability to see things beyond what you already know and believe. You also need to have a clean soul in order to look at things with a fresh perspective. 

Because the vietnam war was fought in an especially brutal and untraditional way

The answer is d. prior knowledge. she breaks it into parts in order to figure out what other words have the same parts to the word and put the meanings together.