Final answer:
A puzzle is the best example of agitation.
Step-by-step explanation:
The best example of agitation among the given options is A puzzle. Agitation refers to a state of restlessness or excitement, and solving a puzzle often involves feeling agitated as you try to figure out the solution. The other options, such as a prize-winning newspaper article or a biography of the President, may evoke other emotions, but they do not necessarily represent agitation.