Experts solve this and show the workings clearly

Dear Student,
​​​​​​The over valued price of furniture is Rs 240000. 
Let the actual value of furniture be x .
x+20%of x=240000.
$$\begin{gathered} \frac{120x }{100}=240000 \\ x=\frac{240000\times 100}{120}=200000 \end{gathered}$$
Therefore original value of furniture =200000 and hence the extra 40000 will be credited to furniture account.
So option A is the right answer.
Regards