Which Statement Is an Accurate Description of the Brain Activity

Which statement is an accurate description of the brain activity of participants in Qin,et al.'s (2003) study of mental activity during problem solving?

A) With expertise,the amount of brain activity necessary to solve a problem decreases.
B) Expertise in problem solving serves to tone the brain and make activation of specific brain regions involved in this activity occur more quickly.
C) Overall,brain activity during problem solving increases with greater expertise.
D) Expertise is not a factor in the amount of brain activity during problem solving;fatigue is a much more salient variable.