Which of the following is considered a risk factor for the development of malignant melanoma?

The correct choice identifies the inability to tan as a risk factor for the development of malignant melanoma. This characteristic is significant because individuals who cannot tan typically have lighter skin, which contains less melanin. Melanin provides some protection against the harmful effects of ultraviolet (UV) radiation from sun exposure. When skin that cannot tan is exposed to UV radiation, it is more susceptible to DNA damage and, ultimately, the development of skin cancers, including malignant melanoma.

In contrast, the other characteristics listed do not significantly increase the risk for malignant melanoma. For example, while male gender has been associated with higher rates of melanoma compared to females, it is not as direct a risk factor as skin type and tanning ability. Additionally, Japanese ethnicity typically has a lower incidence of melanoma due to genetic factors and skin pigmentation. Similarly, having brown hair does not inherently confer a notable risk factor for melanoma. The primary concern in the context of melanoma development often revolves around skin type and tanning ability, emphasizing the importance of the ability (or inability) to tan in relation to skin cancer risk.