Which of the following is a common cause of acne?

Hormonal changes that increase sebum production are a common cause of acne because they lead to an overproduction of oil in the skin. This excess oil can clog pores, along with dead skin cells and bacteria, resulting in the formation of acne lesions. Hormonal fluctuations, particularly those related to puberty, menstruation, or hormonal conditions such as polycystic ovary syndrome (PCOS), can significantly contribute to the severity of acne.

When comparing this to the other choices, excessive exfoliation can strip the skin of necessary oils, potentially leading to irritation rather than acne. Poor hydration is typically associated with dry skin, which is not a direct cause of acne, as acne-prone skin can sometimes be oily. Using non-comedogenic products is actually recommended to help prevent acne, as these formulations are designed not to clog pores. Therefore, the focus on hormonal changes and their effect on sebum production makes this the most accurate answer regarding common causes of acne.