Hopeful.
Why because Enthusiastic can be describe as eager or enjoyment, interest or approval.
I'll answer this question based on the definition of an objective summary (a summary having no signs of bias or opinion).
So the sentence that best describes the example of an objective summary is:
"<span>Using Colorado Springs as his focal point, Mr Schlosser takes the reader on a behind-the-scenes tour of the fast-food industry that includes slaughterhouses, poultry processors, artificial flavors."
Hope my answer has helped you.</span>
I would say the answer is C.
