Final answer:
The sentence should be corrected to "This year has been great, but surely my freshman year of college will be even more fun." (option B) a to fix the incorrect comparative form of 'fun'.
Step-by-step explanation:
The change that should be made to the sentence "This year has been great, but surely my freshman year of college will be even funner." is to correct the comparative form of the adjective fun. The proper comparative form of fun is "more fun", not "funner". Therefore, the corrected sentence should read: "This year has been great, but surely my freshman year of college will be even more fun." This revision addresses comparative adjective use and ensures the sentence adheres to standard English grammar.