You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Charleston,_South_Carolina

Context:
The Charleston-North Charleston-Summerville Metropolitan Statistical Area consists of three counties: Charleston, Berkeley, and Dorchester. As of the 2013 U.S. Census, the metropolitan statistical area had a total population of 712,239 people. North Charleston is the second-largest city in the Charleston-North Charleston-Summerville Metropolitan Statistical Area and ranks as the third-largest city in the state; Mount Pleasant and Summerville are the next-largest cities. These cities combined with other incorporated and unincorporated areas along with the city of Charleston form the Charleston-North Charleston Urban Area with a population of 548,404 as of 2010. The metropolitan statistical area also includes a separate and much smaller urban area within Berkeley County, Moncks Corner (with a 2000 population of 9,123).

Question:
Charleston and Berkeley is combined with what other county to form a metropolitan statistical area?

Dorchester