### Solution:

Concept- An open circuit is defined to be basically a circuit where the energy is not flowing through it. When an electrical circuit is turned on, energy may flow through it, and that circuit is said to be closed. If electricity is moving from an energy source to the intended endpoint of the circuit, the circuit is said to be closed.The 60W bulb has high resistance. If we consider switch 1 closed, the bulb with 120W power will glow instantly and if we close switch 2 then the bulb with 60W power glows. Also, if we close both the switches together then both bulbs will glow simultaneously. If the resistance is low then the 60W bulb will not glow and so the entire circuit will work only for the 120W bulb.

Hence, option 1 is correct.