The correct answer is option D, that is, a storage battery is charged using an electric current.
The transformation of one form of energy into another, generally to transform the energy into more useful kind is known as energy conversion. The energy can neither be created nor be destroyed, it can only be transformed. The different forms of energy comprise light, heat, mechanical, electrical, sound, nuclear, and sound.
In the given question, the charging of a storage battery using electric current is an example of electrical energy being converted into chemical energy.
Answer : The equilibrium will shift in the left direction.
Explanation :
Le-Chatelier's principle : This principle states that if any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.
The given reaction is:
As per question, when we are adding 
then the concentration of is increased on product side then the equilibrium will shift in the direction where decrease of concentration of takes place. Therefore, the equilibrium will shift in the left direction.
Thus, the equilibrium will shift in the left direction.
