13. which one of the following statements is an example of an opinion? a. my son's band performed at the aladdin theatre in portland last night. b. jason has been playing the guitar for more than ten years now. c. the group tends to play alternative music and their own compositions. d. the concert last night was better than any of us expected.

Your question was "Which one of the following statements is an example of an opinion" and reading all of these statements leads me to believe that D is the correct answer.
A. = Fact
B. = Fact
C. = Fact
D. = Opnion

The answer is D because they say "The concert last night was better than any of us expected" it may have not been what that person expected but some others may have. It is their opinion that it was an unexpected turn of events. I hope this helped love!