A nurse is reinforcing discharge teaching with the guardian of a preschooler who has a fiberglass arm cast. Which of the following statements by the guardian indicates an understanding of the teaching?

"I will make sure my child's arm doesn't hang down for more than 30 minutes."

"It is okay to submerge the cast for 5 minutes during my child's bath time."

"I will ensure my child avoids moving their fingers while the cast is in place."

"It is okay to use a pencil to scratch inside my child's cast."