Final answer:
The student is protected on religious grounds based on the case West Virginia v. Barnette, which established the right to freely exercise religious beliefs in schools.
Step-by-step explanation:
In 1940s, the Barnette family sued the West Virginia Board of Education because their religious beliefs clashed with the requirement of standing and reciting the Pledge of Allegiance in school. The case West Virginia v. Barnette established that individuals have the right to freely exercise their religious beliefs, even if it means not participating in patriotic rituals. This protects the student's refusal to salute the flag or recite the Pledge of Allegiance on religious grounds.