Study of kidneys is known as:

Nephrology

The correct answer is Option (4) → Nephrology

The study of kidneys is known as Nephrology.

It is a branch of medicine that deals with the functions and diseases of the kidneys, including diagnosis and treatment of kidney disorders, management of kidney failure, dialysis, and kidney transplantation.

• Odontology: Study of teeth.

• Neurology: Study of the nervous system (brain, spinal cord, nerves).

• Hematology: Study of blood and blood-related disorders.