If m and n are whole numbers such that mn = 121, then the value of (m - 1)n+1 is = ?

Answer: Option D

$$\begin{array}{rl}& \text{We know that}\\ & \text{1}{\text{1}}^2=121\\ & \text{Putting}\\ & m=11\&n=2\\ & \text{we get}\\ & {\left(m-1\right)}^{n+1}\\ & ={\left(11-1\right)}^{\left(2+1\right)}\\ & =10^3\\ & =1000\end{array}$$