C. No one knew germs existed
Therefore diseases spread because they did not know how to prevent them and they did not have good hygiene.
2- 4 glasses, also depends on how old you are
Answer:
Internal can be you don't want bad things happening to your body, you don't want drugs affecting your health,etc.External could be you don't want it to affect your family or people around you.For example, like a cigarette if you are smoking in public you can be affecting others passing by or hanging out with you(external)but if it's just you by yourself smoking it is damaging your lungs(internal)
The answer would be D. 30s (apex)
this is true! someone can have it and not have any presentable symptoms
