According to the passage, some critics believe which of the following about the "government of Getúlio Vargas?" A. It used samba as a symbol of national identity to help to politically empower Afro-Brazilians. B. It used samba as a symbol of national identity to compete with Euro-Brazilian elites for political power. C. It used samba as a symbol of national identity to secure its own political power. D. It attempted to clarify the true origins of samba. E. It resisted the national glorification of samba.