Choose the Answer Which Best Rewords the Italicized Portion

Choose the answer which best rewords the italicized portion. If you think the original wording is best, choose option A.
Some countries such as the United States have ample sources of water.

A) countries such as the United States
B) countries, such as the United States
C) countries, such as the United States,
D) countries, such as the United States;