Given:
The initial resistance of the resistor, R=6 Ω
The resistance of the second resistor, R₀=18 Ω
The initial value of the current is I.
To find:
The ratio of new electric current through the circuit to the initial value of the current.
Step-by-step explanation:
From Ohm's law, The voltage of the battery before the resistance was increased is given by,

The voltage of the battery is also given by,

Where I₀ is the new electric current through the circuit.
From the above two equations,

On substituting the known values,

Final answer:
Thus the ratio of the new value of electricity to the old value of electricity is 1/3
Therefore the correct answer is option C.