we are given
![sin^(-1)(tan((\pi)/(4)))](https://img.qammunity.org/2019/formulas/mathematics/middle-school/uof4il50qayyavw62zrzj8z69o28nude8k.png)
Let's assume entire term as x
![sin^(-1)(tan((\pi)/(4)))=x](https://img.qammunity.org/2019/formulas/mathematics/middle-school/mxxgvzi6785r4tmivzwp801dcpw5ieybwh.png)
now, we can take both sides as sin
![sin(sin^(-1)(tan((\pi)/(4))))=sin(x)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/t2un993wbkt5jmhdf7rgvz1w7tp0iedptc.png)
since, sin and sin^-1 are inverse of each other
so, they will get cancelled
and we get
![tan((\pi)/(4))=sin(x)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/r44zq4uozz5n35xc7joocojvdmqig7jcgm.png)
now, we know that
tan(pi/4)=1
![1=sin(x)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/9l6yf13896hwjxzoe9gyvnjwynx5z1ptv2.png)
and sin is 1 at pi/2
so, we get
![x=(\pi)/(2)](https://img.qammunity.org/2019/formulas/mathematics/high-school/k5f2uxaat7i6wn5sulrn0fi5sl3xigtjpy.png)
so, option-D.........Answer