Final answer:
The cephalic vein is the most common second choice for drawing a blood sample after the median cubital vein.
Step-by-step explanation:
After the median cubital vein, the most common second choice for drawing a blood sample is the cephalic vein. The cephalic vein is a superficial vein in the arm that parallels the ulnar vein and continues into the upper arm. It is often visible along the surface of the biceps brachii muscle and is frequently used for blood draws.