I believe it is D, all of these. :) I hope this helps! Please tell me if I'm wrong :)
Answer:
ph is unit of measuring acid and base
if ph is less than 7 it is acid and ph is more than 7 it is base
It needs at least 4 hours to grow to cause illness :)
Cm3 unless its luiquid right
? hope this helps
Changes in temperature, salt concentration, ionic concentration, of pH levels