The correct answer is C. Delusional thoughts and behaviors
Step-by-step explanation:
Aging implies multiple changes including physical and cognitive decline. Due to this, the elderly around the age of 100 are expected to experience some cognitive declines and functional or physical declines. Also, it is common they lost interest in many activities including basic ones such as eating. However, delusions (false beliefs or inability to know what is unreal) is not an expected change. Indeed, delusional thoughts and behavior only occur if there are diseases such as Alzheimer's disease but are not an expected or normal change associated with aging.