The Parent of a Child Diagnosed with Tourette's Disorder Says

The parent of a child diagnosed with Tourette's disorder says to the nurse, "I think my child is faking the tics because they come and go." Which response by the nurse is accurate?

A) "Perhaps your child was misdiagnosed."
B) "Your observation indicates the medication is effective."
C) "Tics often change frequency or severity. That does not mean they aren't real."
D) "This finding is unexpected. How have you been administering your child's medication?"