I believe it is the nervous system but I'm not 100% sure
High homocysteine levels in the blood can damage the lining of the arteries. High levels may also make the blood clot more easily than it should. This can increase the risk of blood vessel blockages. A clot inside your blood vessel is called a thrombus. A thrombus can travel in the bloodstream. From there, it can get stuck in your:
Lungs (called a pulmonary embolism).
Brain (which can cause a stroke).
Heart (which can cause a heart attack).
The answer is A. Mostly occurs in individual sports
It could happen on team sport as well as any individual sport. For Example is Rugby. Rugby is a team- fast paced sports that require its players to do a lot of stopping/twisting movement
