Why was Gavin Grimm prevented from using the bathroom?

Choices:
A. Because he did not belong there
B. Because it was not a match with his born gender
C. not enough information
D. Because he was protesting
Because it was not a match with his born gender
A school board in the eastern state of Virginia has filed an emergency appeal to the U.S. Supreme Court to halt a ruling that allows a transgender student to use the boys’ restroom next school year.
The Gloucester County School Board is trying to prevent Gavin Grimm from using the bathroom that matches his gender identity when school resumes later this year, saying it will "put parents' constitutional rights in jeopardy.''
Grimm sued the school district last year for the right to use the boys’ restroom after the school board enacted a policy limiting bathroom use to the one corresponding with a person’s biological sex rather than the gender with which the student identifies.
Grimm was born female but identifies as male.
"Depriving parents of any say over whether their children should be exposed to members of the opposite biological sex, possibly in a state of full or complete undress, in intimate settings deprives parents of their right to direct the education and upbringing of their children,'' attorneys for the school board wrote.
The ACLU, which is defending Grimm, has argued that forcing him to use the girls' bathroom is a violation of Title IX and the equal protection clause of the 14th Amendment to the U.S. Constitution.
The issue is one that has been hotly debated in schools, courts and state legislatures across the U.S.
The Obama administration in May directed the nation’s public schools to allow transgender students to use bathrooms and locker rooms that match their gender identity or risk losing their federal funding. Twenty-one states have sued to overturn the directive.
The 4th Circuit Court of Appeals sided with Grimm in April. The court reinstated Grimm's Title IX claim and sent it back to the district court for further consideration.
The school board wants the Supreme Court to put Grimm's district court case on hold until the justices decide whether to review the appeals court decision. The board says it plans to file its petition for Supreme Court review by late August.