Respuesta :
Melanin helps protect the skin against effects of the sun such as skin cancers and premature aging. In African American skin, melanin provides a sun protection factor (SPF) equivalent to 13.4 compared to 3.4 in white skin and thus the former have lower incidences of skin disorders associated with exposure to the sun.
The answer is:
A) The polygenic trait appeared as incomplete dominance.
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