A stone of mass $1kg$is raised through $1m$a height

The correct option is D

The gain of gravitational potential energy is $9.8joule$

Step 1: According to the question we have

Mass of stone $m=1kg$

Height$h=1m$

Step 2: Calculating the potential energy,

Potential energy$=mgh$

$$\begin{gathered} \Rightarrow 1kg\times 9.8\raisebox{1ex}{$m$}\!\left/ \!\raisebox{-1ex}{$s^2$}\right.\times 1m \\ \Rightarrow 9.8kg{m}^2{s}^{-2} \\ \Rightarrow 9.8joule \end{gathered}$$

Thus, we conclude that the gain of gravitational potential energy is $9.8joule$.

Hence, option D is the correct answer.