Which of the Following Is an Example of Solidarity

Which of the following is an example of solidarity?

A) When members of an anti-gay church show up at a local high school football game to protest the inclusion of a gay athlete on the team, every student in the school showed up to counter-protest, arguing that an attack on one of them was an attack on all of them.
B) When telecommunication workers went on strike, many of the employees in the office refused to participate in the picket and went to work rather than joining in the strike.
C) After her elderly father passed away, Cynthia received a card from the funeral home expressing their sympathy for her loss.
D) After Jack was confronted by his co-workers about his drinking while on the job, he insisted that such behavior was "no big deal" because "lots of people in other cultures drink while at work."