Answer:
C. One citizen supported a war, while another joins a protest against it.
Step-by-step explanation:
For a situation to be of differing viewpoints, it has to have a contrasting subject. A musician wining an award while one doesn't is in no way contrasting point of view. Likewise, One politician gets elected while another is defeated or one employee gets a higher salary than the other are not about any contrasting viewpoint.
But, a citizen supporting war while another protests is a sure form of differing points of view. Because it constitutes the issues of political issues. The other options are not based on any personal viewpoint, more on the performance of the persons involved. But wars and its issues are based on the opinions of the people and they are contrasting, thus making it a different viewpoint.