Read the following context and choose the best option to answer the question.
Context: First generation biofuels are n't enough and second generation probably are n't either - plus they wo n't be ready . One can use oil shales and I was unhappy to see shale mentioned in the speech . Even with tax credits for cars wo n't change the fleet quickly - that will take a couple of decades .
Question: What type of subject is the narrator interested in ?
Options: 
A. They are interested in taxes .
B. They are interested in consumption of energy .
C. They are interested in sports fuel .
D. None of the above choices .


B