When is a reduced fare available on the transit system?

The correct answer highlights that a reduced fare is available specifically for seniors and certain disabled persons. This policy is designed to provide financial assistance to these groups, recognizing that they may have limited income or resources. The Chicago Transit Authority aims to make public transportation more accessible for those who may otherwise find it challenging to afford regular fare prices.

While other options might suggest various conditions under which fares could be lowered, they do not align with the regulations set by the transit authority regarding who qualifies for reduced fares. For instance, reduced fares are not universally available during peak hours, nor are they simply given to anyone with a student ID or in conjunction with a discount card, unless those cards pertain to approved programs specifically aimed at seniors and disabled individuals. Thus, the emphasis on seniors and certain disabled persons as the qualifying groups for reduced fares is what makes this answer correct.