[单选题]
Light of wavelength 550 nm in air is * bgvmfe 6a qh)u42li8fouz m,j4p0q6s+ou:m wy wnd to travel at $1.96 \times 10^8 \; m/s$ in a certain liquid. Determine the frequency of the light in the liquid.
A. $5.5 \times 10^{14} \; Hz$
B. $3.6 \times 10^{14} \; Hz$
C. $5.5 \times 10^{5} \; Hz$
D. $3.6 \times 10^{5} \; Hz$
