Answer:
Among the different modes used to persuade an audience, in this example we can clearly identify the exercise of "Ethos and Pathos" as form of rhetoric.
The mode "Ethos" is used to build an argument on ethics or the credibility of someone, explicit on "As a volunteer for the Peace Corps, Samuel Eddens saw..."
and the mode "Pathos", a word from Greek origins which means "suffering" and root of words like"Empathy", is used to build arguments relaying on strong emotions such as compassion, explicit on "...their eyes as they silently begged for help". Thereby the answer is (A.)
Explanation: