The product of excretion common to the mammalian kidney, lung and skin is

The question is asking about a common product of excretion in three different organs of mammals: the kidney, lung, and skin. The options are mineral salt, carbon (IV) oxide, water, and urea.

The kidney is responsible for filtering waste products from the blood, including excess water and salts. The lungs remove carbon dioxide, which is a waste product of respiration, from the body. The skin also plays a role in removing waste products, specifically water and salts through sweat.

Out of the four options provided, the correct answer is C: water. Water is a byproduct of many metabolic processes in the body and is excreted through various organs, including the kidney, lung, and skin. While the other options may also be excreted by these organs, water is the only product that is common to all three.

It is important to note that the body excretes a variety of waste products, including urea, which is a byproduct of protein breakdown and is primarily excreted by the kidneys. However, urea is not a product that is common to all three organs mentioned in the question.

In summary, the common product of excretion in the mammalian kidney, lung, and skin is water.