Answer: option B) Secretin
Explanation:
Secretin is an enzyme formed by the upper intestinal layer and gets transported by blood to the PANCREAS which it stimulates: causing the flow of pancreatic juice, also the flow of bile and intestinal juice but to a lesser extent.
Alongside Gastrin, Secretin is one of the hormones of the Gastrointestinal tract; but their functions differ
Therefore, Secretin is the answer
They have evolved into the best length for their environment.
I believe you mean mid-ocean ridge?
If so, true.
A mid-ocean ridge or mid-oceanic ridge is an underwater mountain range, formed by plate tectonics.
This uplifting of the ocean floor occurs when convection currents rise in the mantle beneath the oceanic crust and create magma where two tectonic plates meet at a divergent boundary.
A mid-ocean ridge demarcates the boundary between two tectonic plates, and consequently is termed a divergent plate boundary.