[单选题]
What happens to the cyclotrae.y hox l(3+lon frequency of a charged partif re.q3ml m:s-j arg-nl9t 3twka:*-lcle if the radius of its path doubl ae jrnml 33g - frt-ml9t:sq:w*ak-.les?
A. It triples.
B. It doubles.
C. It halves.
D. It does not change.
