[单选题]Which of the following statements about Roman Britain is true?（2012.4真题）
AThe Romans remained in control of Britain
for over 500 years.b.The Romans never treated the Britons as a
subject people of slave class.c.During the four centuries, Romans
Britons had a lot of intermarriages.d.The Romans had no impact on the language
or culture of ordinary Britons.
