Preliminary, non-experimental, research that gathers information about behavior is called 
research.
Answer:
PTSD
Explanation:
"Post Traumatic Stress Disorder is a mental health condition that's triggered by a terrifying event — either experiencing it or witnessing it. Symptoms may include flashbacks, nightmares and severe anxiety, as well as uncontrollable thoughts about the event."
Read more at https://www.mayoclinic.org/diseases-conditions/post-traumatic-stress-disorder/symptoms-causes/syc-20355967
The answer is A. Quit smoking.
Smoking affects the lungs terribly which can greatly affect your heart since they are both part of the cardiovascular system.
EDIT: To further explain, smoking affects your respiratory system (lungs, bronchioles, etc.) however the cardiovascular system depends on the respiratory system. Overall they both keep blood flowing through the arteries of the body. Smoking damages the lining of your arteries, leading to a build up of fatty material which narrows the artery.
Hypothermia is when your core temperature becomes very low.
A. Otc drugs are usually weaker than prescription drugs
