12. What words in this passage provide a positive and enthusiastic tone?

"Geothermal power has exciting potential as a cost-effective, environmentally friendly energy source. If we want to reduce our reliance on fossil fuels, this clean natural resource is the ideal replacement."

A. Word choices such as "potential" and "fuels" contribute to the positive tone.
B. Word choices such as "clean" and "replacement" contribute to the positive tone.
C. Word choice such as "reduce" contributes to the positive tone.
D. Word choices such as "exciting," "clean," and "environmentally friendly" contribute to the positive tone.