Final answer:
A key element of the ACA is the requirement for insurers to cover dependent children up to age 26, allowing them to stay on their parents' plans.
Step-by-step explanation:
One element of Obama's Patient Protection and Affordable Care Act (ACA) is that it required all insurers to cover dependent children up to age 26. This provision allowed young adults to remain on their parents' health insurance plans as they transition into the workforce, providing a critical safety net during a pivotal stage of life. This patient-centric feature aimed to reduce the number of uninsured young adults and was among the popular aspects of the ACA.