Volume of urine is regulated by

Vasopressin is a hormone that is present in the human body. It works primarily on the kidneys and activates the distal convoluted tubules and enables them to reabsorb water and electrolytes, which decreases the loss of water in the form of urine. 

Vasopressin is also called the antidiuretic hormone or ADH. This hormone prevents excessive loss of water from the body. 

Hence the correct option is D.