If an alien meets all the eligibility criteria but lacks an immigrant visa, what happens?

The correct answer highlights that even if an alien meets all eligibility criteria but lacks an immigrant visa, there may still be alternative pathways or provisions under U.S. immigration law that could allow them to adjust their status or obtain legal residency. U.S. immigration law is complex and contains various avenues for individuals to regularize their status. For instance, options such as applying for asylum, demonstrating eligibility for certain waivers, or seeking other forms of relief might still be available.

It's important to recognize that not having an immigrant visa does not automatically eliminate all chances for the alien; instead, it often means they might need to explore different avenues specific to their situation. This aspect of immigration law emphasizes the importance of understanding the nuances of eligibility and various potential options available to individuals.

The other choices indicate a more definitive consequence that may not reflect the flexibility possible within immigration law. While an application could be denied without an immigrant visa, and leaving the country might be a requirement in specific situations, these outcomes do not take into account the other potential legal avenues available to the individual in question. Thus, the nuances of the law provide a broader context that allows for continued eligibility under different provisions, supporting the response provided.