The Adult Child of a Patient Who Is 82 Years

The adult child of a patient who is 82 years of age tells the nurse, "When I ask my dad to do something, it takes him a long time to respond to me. But he does do what I ask." Which is the most appropriate response by the nurse?

A) "At this age, your dad does not have the same intelligence he had when he was younger."
B) "He may be embarrassed because it is difficult for him to learn new things at this age."
C) "Reaction time slows in older adults, so it takes him more time to process your requests."
D) "It is likely that some dementia is developing because this is a normal occurrence in his age group."