The artery lies on the boundary between the cortex and medulla of the kidney.

Arcuate artery

Explanation:

The arcuate artery is a vessel of the renal circulation (in the kidney). It is the artery that is located at the border of the renal cortex and renal medulla. They are shaped like arcs to fit in with the shape of the renal medulla hence the name.

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.