It goes
Cell -> Tissue -> Organ -> Organ System -> Organism
So the answer would system level :)
The difference between pH 3 and pH 4 is a 10 fold difference in the concentration of H+
C2H6 + 4o2 → 2CO2 + 3H2O...
I would <em>PROBABLY</em> say C; Method A is radiation and Method B is conduction. My reason for that is because Method B sounds a lot like conduction to me and Method A sounds like it COULD be radiation? I'm sorry if this is wrong, it just seems like the best choice in my opinion!
