The vibrations of string of length `60 cm` fixed at both ends are presented by the equations
` y = 4 sin ( pi x//15) cos ( 96 pi t)`
where `x and y` are in cm and t in `s`. The maximum displacement at `x = 5 cm` is
A. `2sqrt3cm`
B. `3sqrt2cm`
C. `sqrt2cm`
D. `sqrt3cm`