Indiana State Beauty Practice Exam

The correct answer highlights the primary biological factors contributing to acne. Excess sebum production is a significant cause as sebaceous glands produce oil that helps keep the skin moisturized, but overproduction can result in an oily skin surface. This excess oil can mix with dead skin cells and clog pores, creating an ideal environment for bacteria, particularly Propionibacterium acnes, to thrive. When these bacteria multiply, they can lead to inflammation and infection, which are characteristic of acne.

Other options, while they do affect skin health, are not primary causes of acne in the same way. Although hydration and weather can influence skin behavior, they do not directly lead to acne formation. Similarly, while diet and exercise play roles in overall health and potentially skin clarity, they don't directly cause acne without other contributing factors like those mentioned in the correct answer. Finally, lack of sleep and stress can affect the skin's appearance and trigger flare-ups but are not the primary physiological mechanisms leading to acne development. The focus on sebum, clogged pores, and bacteria is crucial for understanding the core causes of acne.