Question

Which sentence is punctuated correctly?
A.
The three, longest rivers, in United States are the Missouri River, the Mississippi River, and the Yukon River.
B.
The three longest rivers, in United States are the Missouri River the Mississippi River and the Yukon River.
C.
The three longest rivers in United States are the Missouri River the Mississippi River, and the Yukon River.
D.
The three longest rivers in United States are the Missouri River, the Mississippi River, and the Yukon River.

Answer 1

D

Option D correctly uses commas to separate the items in the list (the serial/Oxford comma). (Note: strictly speaking it should read "in the United States," but of the choices given D is punctuated correctly.)