Why does Marx place class struggle at the center of historical development?

Why does Marx place class struggle at the center of historical development? Consider an issue of contemporary concern. What does considering it form the perspective of class struggle reveal? Please note, this essay should cite “The Manifesto of the Communist Party.” It also requires you to do some independent research. Pick a contemporary issue and find, read, and cite three to five newspaper articles about it.  Other writings from Marx and the Calhoun introduction may also be helpful.

*** Use in text citations and provide bibliography
*** Use all material provided then use the internet for the independant research part
*** Answer all questions
*** Clearly state and underline thesis in introduction