The Argon gas trapped between the glass panes to slow the transfer of heat, which insulates the room from the outside heat in the summer and insulates the heat of the room or traps the heat inside the room in the winter.
As the Argon gas is slow-moving gas than the air, thus, the transfer of heat slowly takes place. Thus, Argon gas is a poor conductor or a good insulator.
The gas trapped in between the glass panes contains moisture, that can condense and make the glass panes appear cloudy.
Thus, by adding the Argon gas between the glass panes, the thermal insulation efficiency increases.
Hence, option B is the correct answer.