Where is the skin particularly thick?

The scalp is particularly thick due to its function and the protective role it plays for the head. The scalp comprises several layers, including the dermis and subcutaneous tissue, which together create a robust, protective barrier against external injuries. This thickness offers both cushioning and defense for the underlying structures, making it less susceptible to abrasions and other forms of trauma compared to areas with thinner skin.

In contrast, the other options feature thinner skin. The lips are especially sensitive and have a much thinner dermal layer, which contributes to their high sensitivity but lower protection. The ears also have a thinner skin covering, which can be prone to injury and damage. Eyelids possess delicate skin as well, which allows for greater flexibility and movement but at the cost of thickness and protective capability. Hence, the scalp stands out as the area where the skin is particularly thick, emphasizing its protective role.