It could them know how it start when it started wats in the infectious disease and why
Answer:
DNA
Explanation: Because if you stretch DNA it gets longer.
As a base is added to an acidic solution, the H+ ions in solution that make it acidic are slowly neutralized into water (via OH-, the base). As these ions are converted into water the concentration of them decreases, so the pH decreases, as they are directly related.
Hope this helps!