What is the outcome if an adopted child reaches a certain age and wishes to make medical decisions?

When an adopted child reaches a certain age, typically around the age of 18, they are legally treated as an adult in terms of making their own medical decisions. This means that they may consent independently to medical procedures without needing permission from their adoptive parents or any other guardians.

This reflects a broader principle in family law, where individuals achieve the legal capacity to make such decisions as they reach the age of majority. It recognizes the autonomy and rights of the young adult, allowing them to take responsibility for their healthcare choices and medical treatment.

The other options do not accurately reflect the legal standing of adopted children regarding medical decision-making at adulthood. For instance, the notion that the parents retain all decision-making power would contradict the established legal independence granted to individuals upon reaching adulthood. Case-by-case deliberations by the court do not typically apply to routine medical consent for those of legal age. Lastly, consulting biological parents is not relevant to medical decision-making for an adopted child, as their legal relationship primarily pertains to their adoptive family post-adoption. Hence, option C encapsulates the correct legal framework.