Question 2

@Samir, Let's look at the argument. State researchers have found that since the oil price increases, there has been a decline in home energy consumption. They concluded that almost all of the decline has been achieved through reduced standards of living and changes in the way spend their time. (A) says "sales of portable heaters rose as families concentrated their winter activities in certain rooms." This fact clearly supports the fact that one's standard of living has gone down if they cannot afford to heat their whole house and instead, use a portable heater to heat only a limited space. Since energy consumption by a portable heater is less than a center heater, and the use of portable heaters is associated with a reduced standard of living, this fact supports the conclusion. Does this make sense? Let me know if you have any further questions.

My problem with A is that it does not clarify that they turned their central heater off or for that matter, stopped using their fireplace. Portable heaters use a lot of energy.