Answer :
The answer is B. Three important dates in U.S. history are July 4, 1776, April 9, 1865, and September 11, 2001. Hoped I helped. :)
Answer:
Option B - Three important dates in U.S. history are July 4, 1776; April 9, 1865; and September 11, 2001.
Explanation:
Commas are used in English to separate items, while semicolons are used to join independent clauses.