Which sentence is punctuated correctly? A. Three important dates in U.S. history are July 4; 1776; April 9; 1865; and September 11; 2001. B. Three important dates in U.S. history are July 4; 1776, April 9; 1865, and September 11; 2001. C. Three important dates in U.S. history are July 4, 1776; April 9, 1865; and September 11, 2001. D. Three important dates in U.S. history are July 4, 1776, April 9, 1865, and September 11, 2001.