The Parent of a Child with Tourette's Disorder Says to the Nurse,"I

The parent of a child 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 doesn't mean they aren't real."
D) "This finding is unexpected.How have you been administering your child's medication?"