A glass slab of thickness `4 cm` contains the same number of waves as `5 cm` of water, when both are traversed by the same monochromatic light. If the refractive index of water is `4//3,` then refractive index of glass is
A. `(5)/(3)`
B. `(5)/(4)`
C. `(16)/(15)`
D. `(3)/(2)`