question_answer

If \[{{\sin }^{-1}}\frac{x}{5}+\cos e{{c}^{-1}}\left( \frac{5}{4} \right)=\frac{\pi }{2},\] then a value of x is

A)  1                                

B)  3

C)  4                                

D)  5

E)  None of these