11. A bob is attached to a long, light string. string is deflected by 3 initially with respect to vertical. The length of the string is 1 m. The value of 0 at any time t after the bob released can be approximately 
written as (Use : g = ${\mathrm{\pi }}^2$) 
(A) 3$°$ cos $\mathrm{\pi }$t 
(B) 3$°$ sin $\mathrm{\pi }$t 
(C) 3$°$ sin ($\mathrm{\pi }$t + $\frac{\mathrm{\pi }}{6}$ ) 
(D) 3$°$ cos ($\mathrm{\pi }$t+$\frac{\mathrm{\pi }}{6}$ ) 
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