Final answer:
The requirement that is not necessary to be eligible for a real estate license in Texas is being a U.S. citizen; rather, one must be a lawful permanent resident, among meeting other criteria.
Step-by-step explanation:
The question asks about the requirements for becoming eligible for a real estate license in Texas, except for one option that is not a requirement. Based on the given information, the option that is not a requirement for a real estate license in Texas is being a U.S. citizen. To be eligible for a real estate license in Texas, you need to be at least 18 years old, a legal resident of Texas, and a high school graduate. However, it is not required to be a U.S. citizen; one must be a lawful permanent resident (green card holder) and meet other residency and moral character requirements.