Which of the following statements are true concerning the supreme court's decisions involving symbolic speech?
a. The Supreme Court has generally been supportive of protecting symbolic speech under the First Amendment.
b. The Supreme Court has ruled that certain forms of symbolic speech, such as burning the American flag, are protected under the First Amendment.
c. The Supreme Court has upheld laws that restrict certain forms of symbolic speech, such as banning certain types of protest signs.
d. The Supreme Court has consistently ruled in favor of limiting the protection of symbolic speech under the First Amendment.