Which condition is classified as a congenital defect?

Congenital heart defects are classified as congenital defects because they result from abnormal development of the heart and its structures during embryonic development. These defects can occur during pregnancy and are present at birth, often affecting the normal flow of blood through the heart and the body's circulatory system. They encompass a wide range of heart abnormalities, which can vary in severity and may require various interventions or treatments throughout a person's life.

In contrast, conditions like diabetes, hypertension, and obesity are typically acquired rather than congenital. Diabetes can develop due to lifestyle factors, genetic predisposition, or a combination of both. Hypertension often arises from a variety of factors including lifestyle, age, and other health conditions. Obesity is primarily associated with factors such as diet, physical activity, and genetic influences that lead to an excess accumulation of body fat. Thus, among the options, only a congenital heart defect directly stems from developmental issues occurring before birth.