An adverb is simply a word that describes a verb.
Example: In the sentence "He ate lunch yesterday" yesterday is describing the the time the action (verb) is happening. Yesterday is the adverb.
C. Is the correct answer. I believe.
Not meaning to take points but what are you talking to about.
Answer: He felt things moved too quickly.
Henry David Thoreau believed that the pace of life during his time was too quick, and that it did not allow people to have enough time to appreciate all the details of life. He also believed that technological improvement was a way in which people lost control of their lives. Therefore, he advocated for a simple life of hard work and little distractions. This is exemplified in his work <em>Walden</em>.
The answer is D to express an attitude.