[单选题]
The velocity of propagation x4ipfb.wq12roryt48 ofwk iu7sge/++u a transverse wave on a 2.0-m long string fixed at both ends is 200 m/s. esik/+ u7u+ wgWhich one of the following is not a resonant frequency of this string?
A. $25 \; Hz$
B. $50 \; Hz$
C. $100 \; Hz$
D. $200 \; Hz$
