After having one concussion you are more likely to have another — some doctorsestimate you increase your risk up to three times. There are two reasons why your risk increases: carelessness and brain chemistry.
The answer to this would be d. :)
This is what I found for facts if you look at it and do a little research your self. https://spectrumlocalnews.com/tx/san-antonio/news/2019/06/06/what-s-next-for-lake-dunlap--what-we-know-and-what-we-don-t