The question asks about the substance secreted from oil glands in the body. This question falls under the subject of Home Science, particularly human anatomy related to skin functions.
Explanation:
The skin has several types of glands, with one of them being the oil glands, also known as sebaceous glands. These glands produce a greasy and waxy substance known as sebum.
Sebum: This is the correct answer. Sebum is produced by the sebaceous glands which are located in the dermis layer of the skin. The primary role of sebum is to lubricate and protect the skin and hair by providing a barrier against moisture loss and external irritants.
Urine: Urine is not related to the secretion by oil glands. It is a waste product that is produced by the kidneys and excreted through the urinary system.
Blood: Blood is the life-sustaining fluid that circulates in the cardiovascular system, delivering nutrients and oxygen to tissues, and it is not a secretion of oil glands.
Sweat: Sweat is produced by sweat glands, different from sebaceous (oil) glands. Sweat helps in thermoregulation and is composed mainly of water and salts.
Therefore, the substance secreted from oil glands is sebum.
