Among the following, which condition is most commonly linked to obesity?

Gallbladder disease is indeed the condition most commonly linked to obesity. Excess body weight can lead to the development of gallstones, which are hardened deposits that form in the gallbladder. The risk factors associated with obesity include high cholesterol levels and high fat intake, both of which can contribute to gallstone formation.

As the body mass index (BMI) increases, the likelihood of developing gallbladder disease also rises. This correlation is due to the changes in bile composition and the slowing of gallbladder emptying that can occur with increased body weight. Symptoms of gallbladder disease, such as pain in the upper right abdomen, nausea, and digestive issues, often arise in those who are obese.

Other conditions listed, while associated with obesity, are not as directly linked or prevalent as gallbladder disease. Osteoporosis, for instance, tends to be more common in individuals with lower body weight due to lack of weight-bearing activity and lower calcium intake. Impaired immunocompetence and infertility can indeed be affected by obesity, but they are less frequently observed as common direct consequences compared to gallbladder disease.