Which glands throughout the body primarily excrete water and salt?

Eccrine glands are the primary glands responsible for the excretion of water and salt in the body. These glands are distributed widely across the skin and are particularly abundant in areas such as the palms, soles of the feet, and forehead. Their main function is to regulate body temperature through the process of sweating. When the body heats up, eccrine glands produce a watery sweat, primarily composed of water and salts, which evaporates from the skin surface, helping to cool the body down.

Other gland types serve different functions. Apocrine glands, for instance, are primarily located in areas such as the armpits and groin, and they secrete a thicker fluid that can contribute to body odor when broken down by bacteria. Sebaceous glands are associated with hair follicles and produce an oily substance called sebum, which helps to protect and moisturize the skin but does not excrete water and salt. Endocrine glands produce hormones that regulate various body functions but do not have a direct role in excretory processes like sweating. Therefore, the eccrine glands specifically focus on excreting water and salts, making them the correct answer to this question.