Some causes could be the mother smoking, drinking, doing drugs etc. Or even simply her body doesn’t fully accept the baby growing inside her so it acts out against it. Sounds strange but it happens. Also if the mother is sick with Zika or another virus, it can harm the baby’s growth.
the most often the start of a scientific investigation. is observation
By common logic you know that water has pH=7
When you add water to something that is acidic, for example you add water to vinegar, you make it less acidic. So the pH from 2 will be higher for instance 3 or 4 or 5 etc.
This happens because pH=-log[H3O+]
Explanation:
option A is the correct one.