Critical Reasoning (CR) | Re: Technological improvements and reduced equipment costs have

Technological improvements and reduced equipment costs have made converting solar energy directly into
electricity far more cost-efficient in the last decade. However, the threshold of economic viability for solar power
(that is, the price per barrel to which oil would have to rise in order for new solar power plants to be more
economical than new oil-fired power plants) is unchanged at thirty-five dollars.
Which of the following, if true, does most to help explain why the increased cost-efficiency