Which sentence is punctuated correctly?
A.
My father has studied these languages: Russian; German; and Arabic.
B.
On their vacation trip to Europe, the Richardsons visited Vienna, Austria; Munich, Germany; and Warsaw, Poland.
C.
The dates of the big conventions are May 18-20; July 13-15; and August 17-19.
D.
James City County; Virginia, St. Mary's County; Maryland, and York County; Maine are some of the oldest counties in the United States.