The best answer is C. Tailings are dangerous because they can release toxic elements into the groundwater or surface water. Tailings are the waste materials after the process of extracting the valuable part in a mine. These waste materials have a big potential to destroy the environment because they can release toxic substances which include arsenic and mercury. These tailings can contaminate water bodies.
Steven Jobs spent his childhood in Silicon Valley. He was the type of child who liked to stick to himself. He only did competitive swimming, and no team sports.