Texting and driving because the motorists takes their eyes off the road and realizes that they have to stop at the last minute.
Prejudice is the option B, a negative and unjustly formed opinion, usually against people of a different racial, religious, or cultural group.
Substance abuse such as drugs, alcohol and tobacco, family problems such as domestic violence and abuse, social problems such as peer pressure, bullying, and exclusion, and so many other environmental reasons, but substance abuse, family dysfunction and social problems are the common reasons why.
I would say A because when swimming too fast that can cause cramps and that can cause you to drown some times