What is edema characterized by?

Edema is characterized by fluid accumulation and swelling under the skin. This condition typically occurs when excess fluid builds up in the tissues, leading to noticeable swelling in affected areas. It can result from various factors, including inflammation, injury, or underlying health conditions that affect blood flow or fluid balance in the body.

The other options do not accurately describe edema. Excessive skin dryness refers to a lack of moisture in the skin, which is a completely different condition. Inflammation of internal organs involves the swelling and irritation of those organs, but it does not necessarily lead to the external swelling characteristic of edema. Loss of skin elasticity refers to the skin's decreased ability to return to its original shape, often associated with aging or certain health conditions, and does not involve fluid accumulation. Thus, the defining feature of edema is the presence of excess fluid in tissues, leading to swelling.