Which of the following is a comparatively obvious difference in the contour of the neck between male and female?

A、Vesselsintheneckarevisibleinmalessittingstill;
B、Necksarelongerandslendererinmalesthaninfemales;
C、Thethyroidcartilageismoreapparentinamalethaninafemale;
D、Sternocleidomastoidmusclesareapparentinamalewhenherotateshishead