Who is eligible for testing if they are 22 years old and have never been served in the Intellectual Disability Service system?

The correct answer highlights that individuals who are 22 years old and have never been served in the Intellectual Disability Service system are eligible for testing specifically because they have no prior records of testing. This means that they can seek assessment and potential services tailored to their needs without any existing data that might influence the evaluation process.

The rationale behind this choice is to ensure that individuals who have not yet received any form of support or diagnosis through prior testing can access necessary evaluations that could lead to appropriate services. This focus on those with no previous testing allows for a fresh assessment to be made based on their current situation and needs.

In this context, other options are not applicable since they either include broader criteria that do not align with the specific condition of having never been served or imply a basis for testing that relies on prior history or familial factors, which is not necessary for someone with no history of service in the system.