[单选题]
Figure 11-2 is a "snapshot" of p oauid r:(:t3a1p x3.sgg 9 nttv5nx:a wave at a given tiwew;m* etoj:e9 kru+)me. The frequency of the wave i )tk;rm*+juw9eeewo: s 120 Hz. What is the wavelength?
A. $0.05 \; m$
B. $0.10 \; m$
C. $0.20 \; m$
D. $0.30 \; m$
