I believe that they are becoming more concerned for zoonotic disease because it is becoming more and more common for these animal transmitted disease to spread, such as ringworm or hookworms. The factors that would make these more of a threat would likely be the amount of people with animals or the other animals or people their animals are around or not taking your animal to the vet upon signs of seeing symptoms of declining health.
The best first aid treatment to give a person who have got a stroke and is not in the hospital is to give an intravenous injection of tissue plasminogen activator (tPA). tPA is one of the widely used drug that plays a major role in dissolving the blood clot thereby restoring the blood flow.
We then need to make sure to take the patient to the hospital as soon as possible because longer the period of untreated stroke, more damage to the brain occurs.
B. The air you breathe.
Because the rest of the choices are not environmental factors. Gang activity, and access to jobs and education are not environmental because environment are things about the world.