Final answer:
The Boston police strike of 1919 was likely unpopular due to public fear of violence, disruption, and the association of strikes with communist and radical ideas, as well as support for the firm response by authorities such as Governor Coolidge. The correct option is c).
Step-by-step explanation:
The strike by Boston police in 1919 was unpopular with the public, possibly for several reasons, but most notably due to the violence during the strike and the fear of communism and anarchy.
The general climate in post-World War I America was fraught with tension regarding labor rights, with management often opposed to the demands of workers and the public wary of labor unions and strikes because of their potential for violence and association with radical ideologies.
Governor Calvin Coolidge's firm action in calling out the National Guard to restore order and his refusal to rehire the striking officers was viewed as a strong stance against the threat of communism, earning him public praise.
Strikes in other parts of the country, such as the Great Railroad Strike of 1877 and the Seattle General Strike of 1919, also contributed to a hostile view toward strikes, as both events were marked by violence which left the public less sympathetic to the strikers' causes. Option c) is the correct one.