A sergeant stands too long in the sun and gets confused. His troops are lined up facing north. Then he gives the order to "Right Turn $90^{}\circ$" $$70$$ times, and his troops do so. In which direction are the troops facing at the end? 
选项为:A:$$$$north  B:$$$$east  C:$$$$south  D:$$$$west  E:$$$$west-south-west  请回答其中一个选项.