Parietal cells (also called oxyntic cells) are the stomach epithelium cells which secrete gastric acid. Parietal cells produce gastric acid (hydrochloric acid) in response to histamine (via H2 receptors), acetylcholine (M3 receptors) and gastrin (gastrin receptors).
Answer:
It is D because this would be the appropriate decision to make during exercise. A and C have to do with fashion, and C is a safety hazard.
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