What is one possible theme of A Raisin in the Sun?

Ironically I am reading the same book in my class, and one possible theme is deferred since most dreams in the book got deferred (delayed or halted), for example beaneatha that wanted to attend medical school but the other dude opened up a liquor store and got scammed, that is a dream deferred since it didn't get completed, another example could be Mama's dream where they had to sell the house for money