The answer is:
Machiavelli forces readers to carefully consider the meanings of the words merciful and mercy.
In the passage from "The Prince," the author Niccolò Machiavelli mentions the words mercy and merciful intending to make readers contemplate their meanings with special circumspection. Thus, <em>mercy </em>is compassion towards somebody one can hurt or punish, and <em>merciful </em>means benevolent. In that respect, Machiavelli suggests that an unsympathetic ruler can preserve power rather than a compassionate one.
D is the only sentence with the correct usage of quotation marks.
