Final answer:
Consistent difficulty with complex tasks is an early sign of Alzheimer's disease and should be included in the presentation by the community health nurse to adults with a family history of the disease.
Step-by-step explanation:
An early manifestation of Alzheimer's disease to include in the community health nurse's presentation for adults with a family history of the condition would be c) Consistent difficulty with complex tasks. This symptom aligns with recognized early signs of Alzheimer's, such as disruptive memory loss, confusion about time or place, and challenges in planning or executing tasks. Occasional forgetfulness and age-appropriate memory loss are common in normal aging and are not specific indicators of the disease, whereas a more serious and persistent disruption in handling complex tasks could signal the onset of Alzheimer's. Improved problem-solving skills would not be associated with Alzheimer's, as the disease typically leads to cognitive decline.