I'm not sure if there is an automatic way to adjust the point values, but you can use SpeedGrader to grade the response and adjust the points accordingly.
Good evening, renees...
I am reviewing some of the older questions here in the Community, and I came across your question. I thought I'd check in with you because I noticed we have not heard back from you since you first posted your question on August 30, 2019. It looks like @holly_andrews had replied to you later that afternoon. Have you had a chance to review her feedback? If so, did it help to answer your question? If so, please feel free to click the "Mark Correct" button next to her response. But, if you are still looking for some help with your question, please let us know that as well by posting a message below.
I did look at the Guides for Classic Quizzes and New Quizzes, but I'm not sure that these Guides will help to answer your question (specifically the information in the blue boxes at the top of each of these links):
Since we have not heard back from you and because there hasn't been any new activity in this topic for over five months, I am going to mark your question as "Assumed Answered". However, that will not prevent you or others from posting additional questions and/or comments below that are related to this topic. I hope that's okay with you, Renee. Looking forward to hearing back from you soon.