Question

copyright © mcgraw hill llc. permission required for reproduction or display. multiple choice question which of these is a vein?
o b
o a
jose calvo/alamy stock photo text alternative

Explanation:

To determine a vein, we recall vascular anatomy: Veins typically have thinner walls and larger lumens (inner space) compared to arteries (which have thicker walls, smaller lumens, and more muscle/elastic tissue). In the image, structure A has a larger lumen and thinner wall, consistent with a vein. Structure B has a thicker wall and smaller lumen, typical of an artery.

Answer:

A. A