Context: My husband took me to our car and I sat down and after some time everything was good again . Another time I was sitting in class it was a hot day and everything around me was becoming dark . I put my head down on my desk and then my vision came back .

Question: What may be the reason for them losing their vision ?
Options:
0. They passed out from low blood sugar .
1. They were in an accident .
2. They are dehydrated from the heat .
3. They have a form of genetic blindness .
Answer: 2