as you see you got this problem wrong becuase Its c :)
btw i got same question are we on same schools lol
Answer:
The safety and effectiveness of vaccines are under constant study. Because vaccines are designed to be given routinely during well-child care visits, they must be extraordinarily safe. Safety testing begins as soon as a new vaccine is contemplated, continues until it is licensed, and is monitored indefinitely after licensure.
Explanation:
The fact that gravity exists as it can be repeatedly tested and verified
