Vaccines. Sometimes the patient may be allergic and can not handle the small dose.
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.
Hihi!
The correct answer would be bacteria and in this case streptococcus bacteria!
I hope I helped!
-Loliarual
I believe the answer is (A.)<span>High levels of muscular fitness can improve your self-image and improve or prevent chronic diseases such as diabetes, osteoporosis, and cardiovascular disease. </span>
