The answer is
B. Denaturing proteins
C. Altering quaternary structures
D. Destroying cell membranes
Protein have a complex structure from primary to quaternary structure. Change in pH or temperature will cause denaturation of protein which make it unfolded and change the secondary, tertiary, or quaternary structure and cause the enzyme of bacteria become useless. It could also damage the protein in membrane and destroy them, causing lysis. It should not affect the sugar though
That would be. All of the above.
B a very large molecule made of smaller molecules