Question #N515

Which choice correctly punctuates the following sentence: "I need to buy a new pair of shoes, but I can’t afford them because I already spent too much money on video games and I don’t have a job yet."
A. I need to buy a new pair of shoes, but I can’t afford them, because I already spent too much money on video games and I don’t have a job yet.
B. I need to buy a new pair of shoes but I can’t afford them because I already spent too much money on video games, and I don’t have a job yet.
C. I need to buy a new pair of shoes, but I can’t afford them because I already spent too much money on video games and I don’t have a job yet.
D. I need to buy a new pair of shoes, but I can’t afford them, because I already spent too much money on video games, and I don’t have a job yet.