Final answer:
Obesity is considered a disability under the Americans with Disabilities Act (ADA) if it substantially limits a person's ability to perform major life activities, such as walking or caring for oneself.
Step-by-step explanation:
Under the Americans with Disabilities Act (ADA), a disability is defined as a physical or mental impairment that substantially limits one or more major life activities. Based on this definition, the only option among the given choices that is considered a disability under the ADA is obesity. Obesity can be a disabling condition if it substantially limits a person's ability to perform major life activities, such as walking, breathing, or caring for oneself. For example, if a person's obesity significantly limits their mobility and they are unable to walk without the assistance of a mobility aid such as a wheelchair, they may be considered disabled under the ADA. It is important to note that not all conditions or characteristics listed in the options are considered disabilities under the ADA. Eye color, left-handedness, and cosmetic disfigurement are not considered disabilities under the ADA, as they do not substantially limit major life activities. Substance abuse, while it can be a health issue, is also not considered a disability under the ADA.