In which year did the General Land Office officially open?

The correct answer is 1836. The General Land Office (GLO) was established in the Republic of Texas in 1836, following Texas' independence from Mexico. The GLO's primary purpose was to manage and oversee land grants, surveys, and titles, as well as to facilitate land distribution and development in the newly formed republic. This marked a critical step in organizing land management in Texas, especially as settlers began moving to the region in larger numbers.

In 1836, the responsibilities of the General Land Office included maintaining public records related to land ownership and ensuring that land grants were handled in a systematic manner. The establishment of this office laid the groundwork for future land policies and is an essential aspect of land surveying history in Texas.

The other years mentioned are subsequent to the establishment of the GLO and do not represent the official opening date.