Which test measures the amount of calcium in the blood?

• A. Calcium test
• B. Cholesterol test
• C. Complete blood count
• D. Chest X-ray

Answer: (A)

Measuring the amount of calcium in the blood is done with a calcium test. This laboratory test directly determines how much calcium is present in the serum, usually as total calcium (with ionized calcium also available in some settings). Normal calcium levels are essential for bone health, nerve and muscle function, and blood clotting, and abnormal results can point to issues with the parathyroid, kidneys, or bone/metabolic diseases. The other options serve different purposes: a cholesterol test checks lipid levels in the blood, a complete blood count evaluates blood cells and their components, and a chest X-ray provides an image of chest structures rather than a chemical measurement in the blood.