What structure in the dermis supports hair follicles and glands?

The correct answer is fibrous connective tissue, as it plays a crucial role in supporting the structural integrity of various elements within the dermis, including hair follicles and glands. The dermis is composed primarily of connective tissue, which provides strength and elasticity to the skin. Within this connective tissue, fibroblasts produce collagen and elastin fibers that form a robust matrix, ensuring that hair follicles remain anchored and that glands maintain their structure and functionality. This supportive role is vital for the skin's overall health, as it allows for the proper function of hair growth and secretion of substances by the glands.

Other structures mentioned, like subcutaneous tissue, arterioles, and mesoderm, serve different roles in the body. The subcutaneous tissue primarily acts as an insulating layer and provides cushioning beneath the skin; arterioles are small blood vessels that deliver blood but do not provide structural support; and mesoderm is an embryonic layer that gives rise to various tissues and organs but is not a constituent of the dermis itself. Thus, understanding the function of fibrous connective tissue in the dermis is essential for grasping how skin structures are supported and maintained.