[单项选择]It is often difficult for visitors to understand Americans’ lack of desire for privacy. They are not a nation of walled gardens and closed gates. Their yards normally run into one another without fences;they often visit one another’s homes without being invited or telephoning first; they leave their office doors open while they work. Their lack of desire for privacy probably results from their history as a nation. America is a big country. There have never been walled cities in the United States, nor was there the need for Americans to protect themselves from neighboring states. During the early years, America had so few settlers that neighbors were very important; they were not to be shut out by doors and fences. Neighbors offered protection and helped in the hard work of settling the land. They depended upon each other. From the nation’s early history has come the desire for openness rather than privacy. Visitors will notice this desire in a number of small ways; there may A. they were neighbors B. they were friends C. they depended upon each other D. they got accustomed to that