What does the ceruminous gland secrete?

Keratin is a fibrous structural protein found in hair, skin, and nails, but it is not secreted by ceruminous glands. While keratin may be present in the ear canal due to skin shedding, it is not a product of the ceruminous glands themselves. This choice incorrectly attributes a function that does not align with the role of ceruminous glands.

Mucus is produced by mucous membranes, not by ceruminous glands. Its primary function is to trap pathogens and particles in various body systems, particularly in the respiratory and digestive tracts. Therefore, associating mucus with ceruminous gland activity is incorrect, as these glands do not secrete mucus.

Sebum is an oily substance produced by sebaceous glands, primarily found on the skin and scalp. While ceruminous glands may secrete a waxy substance that can contain oils, the term "oily sebum" specifically refers to the secretion of sebaceous glands, making this choice inaccurate in relation to ceruminous gland function.