How does Cullen express the importance of unity in "Any Human to Another"?

A- by discussing the success of communities that band together in times of sorrow
B- by discussing how ineffective it is to try to get through hard times alone
C- by showing how loneliness and sorrow impact the speaker
D- by exploring how all people are connected by grief and hardship

D- by exploring how all people are connected by grief and hardship.