All of the following are chemical defenses against microbial infection except which of these answers?

• A. Bodily environments with acidic pH to inhibit microbial growth or kill microbes.
• B. Synchronized movement of mucus and microbes within the mucus out of the body.
• C. Bodily fluids containing digestive enzymes to degrade invading microbes.
• D. Positively charged amino acid chains that destroy cell membranes of invading microbes.