【单选题】The stomach produces acids, which denature protein, and pepsin that digests protein. The cell membranes of the epithelial cells lining the stomach contain protein. The protein in the epithelial cells ...
A.
the membranes contain a different type of protein that resists denaturation and digestion.
B.
mucus coats the epithelium.
C.
cell membranes are destroyed but mitotic activity replaces cells with new ones every few hours.
D.
hormones produced by the endocrine cells protect the cell membranes and neutralize the acid pH.