Identify a sign of aging in skin.

Fine lines and loss of elasticity are key indicators of aging skin, representing the natural deterioration of the skin's structure and function over time. As a person ages, the production of collagen and elastin, proteins that provide skin with firmness and flexibility, diminishes. This reduction leads to the formation of fine lines and the sagging appearance associated with older skin. Additionally, loss of elasticity can cause the skin to become less resilient, resulting in wrinkles and creases that become more pronounced over time.

The other options touch on attributes that may not be as directly associated with aging or that can vary with different skin types and conditions. Increased oiliness is often related to younger skin or specific skin conditions, rather than visible signs of aging. Decreased pigmentation typically refers to conditions such as vitiligo or age spots, which can arise due to various factors, but it doesn't represent a universal sign of aging. An enhanced glow could be seen in well-hydrated or healthy skin, but it is not a definitive sign of aging; in fact, as skin ages, it may lose some of its natural radiance due to factors like dryness or environmental damage. Thus, fine lines and loss of elasticity are the most clear and definitive signs of aging in the skin.