It would be B) Pro
Hope this helps you :))
the study of classification is called taxonomy.
Answer:
energy ( heat has energy makes sense to me hope it helps)
Explanation:
Parietal cells secrete acid in response to three types of stimuli:
Histamine, stimulates H2 histamine receptors (most significant contribution).
Acetylcholine, from parasympathetic activity via the vagus nerve and enteric nervous system, stimulating M3 receptors.
