Which areas of the body contain thicker skin?

The correct answer is the soles of the feet and palms of the hands because these areas of the body are designed to withstand increased friction and pressure. The skin in these locations is thicker due to the presence of a robust stratum corneum, which is the outermost layer of skin that provides a protective barrier. This increased thickness is necessary to protect against wear and tear from walking and grasping objects, which places greater demands on the skin in these regions.

In contrast, other areas such as the back and chest do not require the same level of protection and thus have a thinner epidermal layer. The forehead and elbows have some thicker skin, but not to the extent found on the soles and palms, as they are not subjected to the same degree of repetitive friction and impact. Similarly, the thighs and arms have skin that is generally thinner and less specialized compared to the palms and soles. Thus, the soles of the feet and palms of the hands are uniquely adapted to handle the rigors of daily activities, making this the correct choice.