Final answer:
Eccrine sweat glands are the primary glands responsible for thermoregulation, contrary to the claim in the question. Apocrine glands, sebaceous glands, and salivary glands have different functions and are not the main glands for thermoregulation.
Step-by-step explanation:
The eccrine sweat glands are indeed the primary glands involved in thermoregulation. Contrary to the statement in the question, eccrine glands are abundant on the skin's surface and release a hypotonic sweat that is mostly water, which helps regulate body temperature by evaporative cooling. This distinguishes them from apocrine sweat glands, which are associated with hairy areas like armpits and genital regions and are not primarily used for thermoregulation. Apocrine glands produce a sweat that contains organic compounds and are subject to bacterial decomposition, which can lead to body odor. Other glands, such as sebaceous and salivary glands, are not involved in thermoregulation. Therefore, the assertion that eccrine glands are not the primary gland involved in thermoregulation is incorrect.