丙酮在己烷中的λ[img=~/QImg/2013-10-14-10-14-34/image010.jpg]=279nm,ε[img=~/QImg/2013-10-14-10-14-34/image010.jpg]=14.8,判断由哪种跃迁引起的该吸收峰

A、σ→σ[img=~/QImg/2013-10-14-10-14-34/image004.jpg]
B、n→σ[img=~/QImg/2013-10-14-10-14-34/image004.jpg]
C、n→π[img=~/QImg/2013-10-14-10-14-34/image004.jpg]
D、π→π[img=~/QImg/2013-10-14-10-14-34/image004.jpg]