Concept:The option that is not a problem is the one that describes a favourable condition for solar energy use.Explanation:Poor technological know-how is a problem because many places lack the skill to install and maintain solar systems.Unreliability is a problem because solar power depends on weather conditions and daylight hours.Fear of competition with established energy sources is a problem because existing energy industries may resist the growth of solar power.Adequacy of capital means that enough money and resources are available, so it is not a difficulty.Thus, the option that is not a problem is the one referring to sufficient funds.Answer:B. Adequacy of capital