[单选题]
The velocity of propagation of a transverse wave onf5mo x )o+/ayw a 2.tce26uu qlvdaq287 :x0-m long string fixed at both end luv d2:uxta7qq26e8c s is 200 m/s. Which one of the following is not a resonant frequency of this string?
A. $25 \; Hz$
B. $50 \; Hz$
C. $100 \; Hz$
D. $200 \; Hz$