It is impossible to definitively say which country has "darker skin" because skin tone is a spectrum, and variation exists within countries and regions.
However, South Sudan is often cited as a country with some of the world's darkest skin tones. The Dinka and Nuer ethnic groups in South Sudan are known for their deep, dark complexions.
The amount of melanin in a person's skin determines its color, and melanin production is influenced by geographic location and exposure to sunlight. People living near the equator, where UV radiation is intense, have developed darker skin to protect them from the damaging effects of the sun.
It is important to remember that skin color is a complex and diverse characteristic, and generalizations about entire countries should be avoided.
