Biologists Are Studying the Anatomy of a Newly Discovered Whale

Multiple Choice

Biologists are studying the anatomy of a newly discovered whale whose carcass has washed up on shore.In examining a cross section of its flipper,they notice a vein and an artery running in parallel.The artery can be distinguished from the vein because the artery has

A) a larger interior diameter.
B) more muscle tissue and elastin in the wall.
C) a lining of vascular endothelium.
D) valves to prevent backflow.
E) All of the above