What is the age requirement for a parent of a USC to qualify under the IR5 category?

To qualify under the IR5 category, a parent of a U.S. Citizen (USC) must be 21 years of age or older. This age requirement is established by U.S. immigration law, which specifies that only U.S. citizens who are at least 21 can petition for their parents. Therefore, having the minimum age requirement ensures that the USC has reached adulthood and has the legal standing to sponsor their parent for immigration.

The other options fall outside this legal framework. For instance, being under 21 or under 18 would not meet the age requirement necessary for a USC to initiate a petition, and indicating an age of over 30 doesn't align with the specific stipulation of the IR5 category, as the critical requirement is simply being at least 21 years old.