A researcher classifies glands based on whether they use ducts. Which gland would be categorized as endocrine?

• A. Sweat gland that releases perspiration onto the skin surface
• B. Sebaceous gland that secretes oil into hair follicles
• C. Thyroid gland that secretes hormones into nearby capillaries
• D. Pancreatic acinar gland that releases enzymes into the small intestine

Answer: (C)