Which of the following sentences contains the best example of parallel structure? A. The inability of the delegates to the Constitutional Convention to act on the issue of slavery led to nearly 200 years of unrest that came to a head during the civil rights movement. B. Although John F. Kennedy was killed before much of his civil rights program was enacted, his successor, Lyndon B. Johnson, fulfilled his promises of justice for African Americans. C. Baseball player Jackie Robinson, singer Marian Anderson, poet Langston Hughes, and minister Martin Luther King Jr. all played crucial roles in the fight for civil rights. D. Charlayne Hunter-Gault, one of nine brave students who integrated the Little Rock school system, grew up to become an internationally known journalist.