ANS:B - decrease heat loss and will have no effect beyond that.

Up to the critical radius of insulation, added insulation will decrease heat loss and will have no effect beyond that. The critical radius of insulation is the point where further addition of insulation does not result in a significant reduction in heat loss. At this point, the rate of decrease in heat loss slows down, and adding more insulation does not provide additional benefits in terms of reducing heat loss. Beyond the critical radius, additional insulation will have no further effect on reducing heat loss.