What type of tissue do adenomas affect?

Adenomas are benign tumors that arise from glandular tissue, which is specialized epithelial tissue that forms glands capable of secreting substances such as hormones, enzymes, or other fluids. Glandular tissue is primarily composed of epithelial cells, which are organized to carry out secretory functions. When adenomas develop, they typically originate in organs such as the thyroid, pituitary gland, or adrenal glands, where glandular tissue is prevalent.

The other types of tissues listed—nervous, muscle, and epithelial—do not specifically relate to the formation of adenomas in the same way. While epithelial tissue is indeed involved in adenomas (since glandular tissue is a specialized form of epithelial tissue), the most precise answer is glandular tissue, reflecting the specific context in which adenomas occur.