No, it does not have to be listed as a major choice. This from the UT web site: The College of Liberal Arts must be selected as one of the two college choices on ApplyTexas.org. Plan II Honors will appear as a major choice in the College of Liberal Arts major menu. You may note Plan II as a major choice or you may choose any other major in the College of Liberal Arts. Please note that Plan II/College of Liberal Arts DOES NOT need to be the first choice college.
The critical selection of Plan II is on the electronic Honors Application the applicant accesses after submitting ApplyTexas.org. As long as the College of Liberal Arts was selected as one of the college choices on ApplyTexas.org, Plan II will appear as an option on the honors application. The applicant must check Plan II as an honors program choice on the honors application for Plan II Honors to receive the application for admission review.
If Plan II is the only major choice, the applicant will see the major choice reflected on the Web status check as: Liberal Arts “Undeclared” (undeclared major). That is what is supposed to appear. If an applicant is the top 8%, admission may be reflected as “admitted to Liberal Arts/Undeclared” before the applicant receives an admission decision from Plan II Honors.
http://liberalarts.utexas.edu/plan2/admission/application/tips.php