[单选题]
The speed of Halley's Comet, while traveling in its elliptical orbiv6bk5 b-mh5q9nohmm- t ade1xdf7xwjs2 / c358n 0n oibzround the S7 /x1ndin2xc 0o3sjedwz5 b 8fun,
A. is constant.
B. increases as it nears the Sun.
C. decreases as it nears the Sun.
D. is zero at two points in the orbit.
