Type the appositive phrase in this sentence. "cookies with chocolate chunks," the winning recipe, received $100.

Answer is: the winning recipe.
An appositive is a noun or noun phrase that renames another noun right beside it. The appositive can be a short or long combination of words.
Another example: Problem number 19, the final question, was difficult - the final question is the appositive phrase in this sentence. 

Most likely a is the answer - because  you generate   38 atp's but also consume an atp.   each atp gives approx. less than 4 kcal so probably a is the closest answer.