Skin aging may be attributed to which of the following?

Skin aging is primarily characterized by several physiological changes that impact its appearance and function. The correct option highlights the loss of elasticity in the skin, which is a significant factor contributing to the aging process.

As we age, the production of elastin, a protein responsible for skin elasticity and resilience, decreases. This reduction leads to sagging, wrinkles, and a general loss of firmness. The skin also becomes less capable of returning to its original shape after being stretched or pulled. This loss of elasticity is compounded by external factors such as sun exposure, smoking, and environmental pollutants, which can accelerate the breakdown of collagen and elastin fibers.

In contrast, an increase in collagen production, thickening of the dermis, and an increase in skin moisture would generally lead to healthier skin characteristics. Higher collagen levels can improve skin structure, while a thickened dermis often correlates with greater support and cushioning for the skin's surface. Increased skin moisture helps maintain hydration and prevents dryness, both of which are vital for youthful-looking skin. Thus, the loss of elasticity represents a diminished capacity to maintain the skin's structural integrity, making it a leading factor in the visible signs of aging.